diff --git a/bin/daemon.php b/bin/daemon.php
index 8de6e1a4cf..0536814b9a 100755
--- a/bin/daemon.php
+++ b/bin/daemon.php
@@ -88,7 +88,7 @@ if (is_readable($pidfile)) {
 }
 
 if (empty($pid) && in_array($mode, ["stop", "status"])) {
-	Config::set('system', 'worker_daemon_mode', false);
+	DI::config()->set('system', 'worker_daemon_mode', false);
 	die("Pidfile wasn't found. Is the daemon running?\n");
 }
 
@@ -99,7 +99,7 @@ if ($mode == "status") {
 
 	unlink($pidfile);
 
-	Config::set('system', 'worker_daemon_mode', false);
+	DI::config()->set('system', 'worker_daemon_mode', false);
 	die("Daemon process $pid isn't running.\n");
 }
 
@@ -110,7 +110,7 @@ if ($mode == "stop") {
 
 	Logger::notice("Worker daemon process was killed", ["pid" => $pid]);
 
-	Config::set('system', 'worker_daemon_mode', false);
+	DI::config()->set('system', 'worker_daemon_mode', false);
 	die("Worker daemon process $pid was killed.\n");
 }
 
@@ -153,7 +153,7 @@ if (!$foreground) {
 	DBA::reconnect();
 }
 
-Config::set('system', 'worker_daemon_mode', true);
+DI::config()->set('system', 'worker_daemon_mode', true);
 
 // Just to be sure that this script really runs endlessly
 set_time_limit(0);
diff --git a/boot.php b/boot.php
index 92be83ed0e..5f8f3a3be3 100644
--- a/boot.php
+++ b/boot.php
@@ -470,7 +470,7 @@ function get_temppath()
 
 		if (System::isDirectoryUsable($new_temppath)) {
 			// The new path is usable, we are happy
-			Config::set("system", "temppath", $new_temppath);
+			DI::config()->set("system", "temppath", $new_temppath);
 			return $new_temppath;
 		} else {
 			// We can't create a subdirectory, strange.
@@ -563,7 +563,7 @@ function get_itemcachepath()
 		}
 
 		if (System::isDirectoryUsable($itemcache)) {
-			Config::set("system", "itemcache", $itemcache);
+			DI::config()->set("system", "itemcache", $itemcache);
 			return $itemcache;
 		}
 	}
@@ -595,7 +595,7 @@ function get_spoolpath()
 
 		if (System::isDirectoryUsable($spoolpath)) {
 			// The new path is usable, we are happy
-			Config::set("system", "spoolpath", $spoolpath);
+			DI::config()->set("system", "spoolpath", $spoolpath);
 			return $spoolpath;
 		} else {
 			// We can't create a subdirectory, strange.
diff --git a/mod/api.php b/mod/api.php
index 3ed19e75bf..48a1e4d46e 100644
--- a/mod/api.php
+++ b/mod/api.php
@@ -68,7 +68,7 @@ function api_content(App $a)
 			$consumer = new OAuthConsumer($app['client_id'], $app['pw'], $app['redirect_uri']);
 
 			$verifier = md5($app['secret'] . local_user());
-			Config::set("oauth", $verifier, local_user());
+			DI::config()->set("oauth", $verifier, local_user());
 
 			if ($consumer->callback_url != null) {
 				$params = $request->get_parameters();
diff --git a/src/Core/Addon.php b/src/Core/Addon.php
index 6451483682..5f1865b554 100644
--- a/src/Core/Addon.php
+++ b/src/Core/Addon.php
@@ -348,7 +348,7 @@ class Addon
 	 */
 	public static function saveEnabledList()
 	{
-		return Config::set('system', 'addon', implode(',', self::$addons));
+		return DI::config()->set('system', 'addon', implode(',', self::$addons));
 	}
 
 	/**
diff --git a/src/Core/Config.php b/src/Core/Config.php
index 13bd8ddaf6..0dd4b22768 100644
--- a/src/Core/Config.php
+++ b/src/Core/Config.php
@@ -19,22 +19,6 @@ use Friendica\DI;
  */
 class Config
 {
-	/**
-	 * Stores a config value ($value) in the category ($cat) under the key ($key)
-	 *
-	 * Note: Please do not store booleans - convert to 0/1 integer values!
-	 *
-	 * @param string $cat The category of the configuration value
-	 * @param string $key    The configuration key to set
-	 * @param mixed  $value  The value to store
-	 *
-	 * @return bool Operation success
-	 */
-	public static function set($cat, $key, $value)
-	{
-		return DI::config()->set($cat, $key, $value);
-	}
-
 	/**
 	 * Deletes the given key from the system configuration.
 	 *
diff --git a/src/Core/Theme.php b/src/Core/Theme.php
index 7339157af5..76149b7589 100644
--- a/src/Core/Theme.php
+++ b/src/Core/Theme.php
@@ -36,7 +36,7 @@ class Theme
 
 	public static function setAllowedList(array $allowed_themes)
 	{
-		Config::set('system', 'allowed_themes', implode(',', array_unique($allowed_themes)));
+		DI::config()->set('system', 'allowed_themes', implode(',', array_unique($allowed_themes)));
 	}
 
 	/**
diff --git a/src/Core/Update.php b/src/Core/Update.php
index 02a39219a1..5a151b8380 100644
--- a/src/Core/Update.php
+++ b/src/Core/Update.php
@@ -36,7 +36,7 @@ class Update
 		$build = DI::config()->get('system', 'build');
 
 		if (empty($build)) {
-			Config::set('system', 'build', DB_UPDATE_VERSION - 1);
+			DI::config()->set('system', 'build', DB_UPDATE_VERSION - 1);
 			$build = DB_UPDATE_VERSION - 1;
 		}
 
@@ -81,7 +81,7 @@ class Update
 
 		if (empty($build) || ($build > DB_UPDATE_VERSION)) {
 			$build = DB_UPDATE_VERSION - 1;
-			Config::set('system', 'build', $build);
+			DI::config()->set('system', 'build', $build);
 		}
 
 		if ($build != DB_UPDATE_VERSION || $force) {
@@ -110,7 +110,7 @@ class Update
 					for ($x = $stored + 1; $x <= $current; $x++) {
 						$r = self::runUpdateFunction($x, 'pre_update');
 						if (!$r) {
-							Config::set('system', 'update', Update::FAILED);
+							DI::config()->set('system', 'update', Update::FAILED);
 							DI::lock()->release('dbupdate');
 							return $r;
 						}
@@ -126,12 +126,12 @@ class Update
 							);
 						}
 						Logger::error('Update ERROR.', ['from' => $stored, 'to' => $current, 'retval' => $retval]);
-						Config::set('system', 'update', Update::FAILED);
+						DI::config()->set('system', 'update', Update::FAILED);
 						DI::lock()->release('dbupdate');
 						return $retval;
 					} else {
-						Config::set('database', 'last_successful_update', $current);
-						Config::set('database', 'last_successful_update_time', time());
+						DI::config()->set('database', 'last_successful_update', $current);
+						DI::config()->set('database', 'last_successful_update_time', time());
 						Logger::info('Update finished.', ['from' => $stored, 'to' => $current]);
 					}
 
@@ -139,7 +139,7 @@ class Update
 					for ($x = $stored + 1; $x <= $current; $x++) {
 						$r = self::runUpdateFunction($x, 'update');
 						if (!$r) {
-							Config::set('system', 'update', Update::FAILED);
+							DI::config()->set('system', 'update', Update::FAILED);
 							DI::lock()->release('dbupdate');
 							return $r;
 						}
@@ -150,7 +150,7 @@ class Update
 						self::updateSuccessfull($stored, $current);
 					}
 
-					Config::set('system', 'update', Update::SUCCESS);
+					DI::config()->set('system', 'update', Update::SUCCESS);
 					DI::lock()->release('dbupdate');
 				}
 			}
@@ -197,11 +197,11 @@ class Update
 					DI::lock()->release('dbupdate_function');
 					return false;
 				} else {
-					Config::set('database', 'last_successful_update_function', $funcname);
-					Config::set('database', 'last_successful_update_function_time', time());
+					DI::config()->set('database', 'last_successful_update_function', $funcname);
+					DI::config()->set('database', 'last_successful_update_function_time', time());
 
 					if ($prefix == 'update') {
-						Config::set('system', 'build', $x);
+						DI::config()->set('system', 'build', $x);
 					}
 
 					DI::lock()->release('dbupdate_function');
@@ -212,11 +212,11 @@ class Update
 		} else {
 			Logger::info('Update function skipped.', ['function' => $funcname]);
 
-			Config::set('database', 'last_successful_update_function', $funcname);
-			Config::set('database', 'last_successful_update_function_time', time());
+			DI::config()->set('database', 'last_successful_update_function', $funcname);
+			DI::config()->set('database', 'last_successful_update_function_time', time());
 
 			if ($prefix == 'update') {
-				Config::set('system', 'build', $x);
+				DI::config()->set('system', 'build', $x);
 			}
 
 			return true;
diff --git a/src/Core/Worker.php b/src/Core/Worker.php
index da38cba10a..562a17c0a2 100644
--- a/src/Core/Worker.php
+++ b/src/Core/Worker.php
@@ -65,7 +65,7 @@ class Worker
 		// Kill stale processes every 5 minutes
 		$last_cleanup = DI::config()->get('system', 'worker_last_cleaned', 0);
 		if (time() > ($last_cleanup + 300)) {
-			Config::set('system', 'worker_last_cleaned', time());
+			DI::config()->set('system', 'worker_last_cleaned', time());
 			self::killStaleWorkers();
 		}
 
@@ -297,7 +297,7 @@ class Worker
 			$stamp = (float)microtime(true);
 			$condition = ["`id` = ? AND `next_try` < ?", $queue['id'], DateTimeFormat::utcNow()];
 			if (DBA::update('workerqueue', ['done' => true], $condition)) {
-				Config::set('system', 'last_worker_execution', DateTimeFormat::utcNow());
+				DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 			}
 			self::$db_duration = (microtime(true) - $stamp);
 			self::$db_duration_write += (microtime(true) - $stamp);
@@ -343,7 +343,7 @@ class Worker
 
 			$stamp = (float)microtime(true);
 			if (DBA::update('workerqueue', ['done' => true], ['id' => $queue["id"]])) {
-				Config::set('system', 'last_worker_execution', DateTimeFormat::utcNow());
+				DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 			}
 			self::$db_duration = (microtime(true) - $stamp);
 			self::$db_duration_write += (microtime(true) - $stamp);
@@ -1004,7 +1004,7 @@ class Worker
 				return;
 			}
 
-			Config::set("system", "worker_started", time());
+			DI::config()->set("system", "worker_started", time());
 
 			// Do we have enough running workers? Then we quit here.
 			if (self::tooMuchWorkers()) {
diff --git a/src/Database/DBStructure.php b/src/Database/DBStructure.php
index d70f7f4ec6..18832b8e50 100644
--- a/src/Database/DBStructure.php
+++ b/src/Database/DBStructure.php
@@ -260,8 +260,8 @@ class DBStructure
 	public static function update($basePath, $verbose, $action, $install = false, array $tables = null, array $definition = null)
 	{
 		if ($action && !$install) {
-			Config::set('system', 'maintenance', 1);
-			Config::set('system', 'maintenance_reason', DI::l10n()->t('%s: Database update', DateTimeFormat::utcNow() . ' ' . date('e')));
+			DI::config()->set('system', 'maintenance', 1);
+			DI::config()->set('system', 'maintenance_reason', DI::l10n()->t('%s: Database update', DateTimeFormat::utcNow() . ' ' . date('e')));
 		}
 
 		$errors = '';
@@ -522,7 +522,7 @@ class DBStructure
 
 				if ($action) {
 					if (!$install) {
-						Config::set('system', 'maintenance_reason', DI::l10n()->t('%s: updating %s table.', DateTimeFormat::utcNow() . ' ' . date('e'), $name));
+						DI::config()->set('system', 'maintenance_reason', DI::l10n()->t('%s: updating %s table.', DateTimeFormat::utcNow() . ' ' . date('e'), $name));
 					}
 
 					// Ensure index conversion to unique removes duplicates
@@ -574,13 +574,13 @@ class DBStructure
 		}
 
 		if ($action && !$install) {
-			Config::set('system', 'maintenance', 0);
-			Config::set('system', 'maintenance_reason', '');
+			DI::config()->set('system', 'maintenance', 0);
+			DI::config()->set('system', 'maintenance_reason', '');
 
 			if ($errors) {
-				Config::set('system', 'dbupdate', self::UPDATE_FAILED);
+				DI::config()->set('system', 'dbupdate', self::UPDATE_FAILED);
 			} else {
-				Config::set('system', 'dbupdate', self::UPDATE_SUCCESSFUL);
+				DI::config()->set('system', 'dbupdate', self::UPDATE_SUCCESSFUL);
 			}
 		}
 
diff --git a/src/Database/PostUpdate.php b/src/Database/PostUpdate.php
index ae6dd7605c..863e823a13 100644
--- a/src/Database/PostUpdate.php
+++ b/src/Database/PostUpdate.php
@@ -67,7 +67,7 @@ class PostUpdate
 		if (!$end_id) {
 			$r = q("SELECT `id` FROM `item` WHERE `uid` != 0 ORDER BY `id` DESC LIMIT 1");
 			if ($r) {
-				Config::set("system", "post_update_1194_end", $r[0]["id"]);
+				DI::config()->set("system", "post_update_1194_end", $r[0]["id"]);
 				$end_id = DI::config()->get("system", "post_update_1194_end");
 			}
 		}
@@ -90,11 +90,11 @@ class PostUpdate
 			intval($start_id), intval($end_id),
 			DBA::escape(Protocol::DFRN), DBA::escape(Protocol::DIASPORA), DBA::escape(Protocol::OSTATUS));
 		if (!$r) {
-			Config::set("system", "post_update_version", 1194);
+			DI::config()->set("system", "post_update_version", 1194);
 			Logger::log("Update is done", Logger::DEBUG);
 			return true;
 		} else {
-			Config::set("system", "post_update_1194_start", $r[0]["id"]);
+			DI::config()->set("system", "post_update_1194_start", $r[0]["id"]);
 			$start_id = DI::config()->get("system", "post_update_1194_start");
 		}
 
@@ -147,7 +147,7 @@ class PostUpdate
 			}
 		}
 
-		Config::set("system", "post_update_version", 1206);
+		DI::config()->set("system", "post_update_version", 1206);
 		Logger::log("Done", Logger::DEBUG);
 		return true;
 	}
@@ -235,7 +235,7 @@ class PostUpdate
 		}
 		DBA::close($items);
 
-		Config::set("system", "post_update_version_1279_id", $id);
+		DI::config()->set("system", "post_update_version_1279_id", $id);
 
 		Logger::log("Processed rows: " . $rows . " - last processed item:  " . $id, Logger::DEBUG);
 
@@ -254,7 +254,7 @@ class PostUpdate
 				DBA::update('item', $fields, $condition);
 			}
 
-			Config::set("system", "post_update_version", 1279);
+			DI::config()->set("system", "post_update_version", 1279);
 			Logger::log("Done", Logger::DEBUG);
 			return true;
 		}
@@ -369,7 +369,7 @@ class PostUpdate
 		}
 		DBA::close($items);
 
-		Config::set("system", "post_update_version_1281_id", $id);
+		DI::config()->set("system", "post_update_version_1281_id", $id);
 
 		Logger::log("Processed rows: " . $rows . " - last processed item:  " . $id, Logger::DEBUG);
 
@@ -380,7 +380,7 @@ class PostUpdate
 			Logger::log("Updating item-uri in item-content", Logger::DEBUG);
 			DBA::e("UPDATE `item-content` INNER JOIN `item-uri` ON `item-uri`.`uri` = `item-content`.`uri` SET `item-content`.`uri-id` = `item-uri`.`id` WHERE `item-content`.`uri-id` IS NULL");
 
-			Config::set("system", "post_update_version", 1281);
+			DI::config()->set("system", "post_update_version", 1281);
 			Logger::log("Done", Logger::DEBUG);
 			return true;
 		}
@@ -417,7 +417,7 @@ class PostUpdate
 
 		Logger::info('Processed rows: ' . DBA::affectedRows());
 
-		Config::set('system', 'post_update_version', 1297);
+		DI::config()->set('system', 'post_update_version', 1297);
 
 		Logger::info('Done');
 
@@ -451,7 +451,7 @@ class PostUpdate
 		}
 
 		DBA::close($contact);
-		Config::set('system', 'post_update_version', 1322);
+		DI::config()->set('system', 'post_update_version', 1322);
 
 		Logger::info('Done');
 
@@ -495,12 +495,12 @@ class PostUpdate
 		}
 		DBA::close($items);
 
-		Config::set('system', 'post_update_version_1329_id', $id);
+		DI::config()->set('system', 'post_update_version_1329_id', $id);
 
 		Logger::info('Processed', ['rows' => $rows, 'last' => $id]);
 
 		if ($start_id == $id) {
-			Config::set('system', 'post_update_version', 1329);
+			DI::config()->set('system', 'post_update_version', 1329);
 			Logger::info('Done');
 			return true;
 		}
diff --git a/src/Model/GServer.php b/src/Model/GServer.php
index 97d679b7e4..7bb9efaffc 100644
--- a/src/Model/GServer.php
+++ b/src/Model/GServer.php
@@ -1429,6 +1429,6 @@ class GServer
 			}
 		}
 
-		Config::set('poco', 'last_federation_discovery', time());
+		DI::config()->set('poco', 'last_federation_discovery', time());
 	}
 }
diff --git a/src/Module/Admin/Blocklist/Server.php b/src/Module/Admin/Blocklist/Server.php
index d6c3daf839..652439efcc 100644
--- a/src/Module/Admin/Blocklist/Server.php
+++ b/src/Module/Admin/Blocklist/Server.php
@@ -27,7 +27,7 @@ class Server extends BaseAdminModule
 				'domain' => Strings::escapeTags(trim($_POST['newentry_domain'])),
 				'reason' => Strings::escapeTags(trim($_POST['newentry_reason']))
 			];
-			Config::set('system', 'blocklist', $blocklist);
+			DI::config()->set('system', 'blocklist', $blocklist);
 			info(DI::l10n()->t('Server domain pattern added to blocklist.') . EOL);
 		} else {
 			// Edit the entries from blocklist
@@ -43,7 +43,7 @@ class Server extends BaseAdminModule
 					];
 				}
 			}
-			Config::set('system', 'blocklist', $blocklist);
+			DI::config()->set('system', 'blocklist', $blocklist);
 			info(DI::l10n()->t('Site blocklist updated.') . EOL);
 		}
 
diff --git a/src/Module/Admin/DBSync.php b/src/Module/Admin/DBSync.php
index cfa6f8d83a..e4382319c9 100644
--- a/src/Module/Admin/DBSync.php
+++ b/src/Module/Admin/DBSync.php
@@ -24,10 +24,10 @@ class DBSync extends BaseAdminModule
 			// @TODO: Replace with parameter from router
 			$update = intval($a->argv[3]);
 			if ($update) {
-				Config::set('database', 'update_' . $update, 'success');
+				DI::config()->set('database', 'update_' . $update, 'success');
 				$curr = DI::config()->get('system', 'build');
 				if (intval($curr) == $update) {
-					Config::set('system', 'build', intval($curr) + 1);
+					DI::config()->set('system', 'build', intval($curr) + 1);
 				}
 				info(DI::l10n()->t('Update has been marked successful') . EOL);
 			}
@@ -40,8 +40,8 @@ class DBSync extends BaseAdminModule
 				$retval = DBStructure::update($a->getBasePath(), false, true);
 				if ($retval === '') {
 					$o .= DI::l10n()->t("Database structure update %s was successfully applied.", DB_UPDATE_VERSION) . "<br />";
-					Config::set('database', 'last_successful_update', DB_UPDATE_VERSION);
-					Config::set('database', 'last_successful_update_time', time());
+					DI::config()->set('database', 'last_successful_update', DB_UPDATE_VERSION);
+					DI::config()->set('database', 'last_successful_update_time', time());
 				} else {
 					$o .= DI::l10n()->t("Executing of database structure update %s failed with error: %s", DB_UPDATE_VERSION, $retval) . "<br />";
 				}
@@ -63,13 +63,13 @@ class DBSync extends BaseAdminModule
 						$o .= DI::l10n()->t("Executing %s failed with error: %s", $func, $retval);
 					} elseif ($retval === Update::SUCCESS) {
 						$o .= DI::l10n()->t('Update %s was successfully applied.', $func);
-						Config::set('database', $func, 'success');
+						DI::config()->set('database', $func, 'success');
 					} else {
 						$o .= DI::l10n()->t('Update %s did not return a status. Unknown if it succeeded.', $func);
 					}
 				} else {
 					$o .= DI::l10n()->t('There was no additional update function %s that needed to be called.', $func) . "<br />";
-					Config::set('database', $func, 'success');
+					DI::config()->set('database', $func, 'success');
 				}
 
 				return $o;
diff --git a/src/Module/Admin/Features.php b/src/Module/Admin/Features.php
index 374fd98f21..79d6e43f5e 100644
--- a/src/Module/Admin/Features.php
+++ b/src/Module/Admin/Features.php
@@ -29,10 +29,10 @@ class Features extends BaseAdminModule
 				} else {
 					$val = 0;
 				}
-				Config::set('feature', $feature, $val);
+				DI::config()->set('feature', $feature, $val);
 
 				if (!empty($_POST[$featurelock])) {
-					Config::set('feature_lock', $feature, $val);
+					DI::config()->set('feature_lock', $feature, $val);
 				} else {
 					Config::delete('feature_lock', $feature);
 				}
diff --git a/src/Module/Admin/Logs/Settings.php b/src/Module/Admin/Logs/Settings.php
index 98bb9b301a..b4c1864ff6 100644
--- a/src/Module/Admin/Logs/Settings.php
+++ b/src/Module/Admin/Logs/Settings.php
@@ -28,9 +28,9 @@ class Settings extends BaseAdminModule
 				return;
 			}
 
-			Config::set('system', 'logfile', $logfile);
-			Config::set('system', 'debugging', $debugging);
-			Config::set('system', 'loglevel', $loglevel);
+			DI::config()->set('system', 'logfile', $logfile);
+			DI::config()->set('system', 'debugging', $debugging);
+			DI::config()->set('system', 'loglevel', $loglevel);
 		}
 
 		info(DI::l10n()->t("Log settings updated."));
diff --git a/src/Module/Admin/Site.php b/src/Module/Admin/Site.php
index 88c62486bb..915eaa5046 100644
--- a/src/Module/Admin/Site.php
+++ b/src/Module/Admin/Site.php
@@ -93,7 +93,7 @@ class Site extends BaseAdminModule
 			update_table($a, "gcontact", ['connect', 'addr'], $old_host, $new_host);
 
 			// update config
-			Config::set('system', 'url', $new_url);
+			DI::config()->set('system', 'url', $new_url);
 			DI::baseUrl()->saveByURL($new_url);
 
 			// send relocate
@@ -232,7 +232,7 @@ class Site extends BaseAdminModule
 
 		// Has the directory url changed? If yes, then resubmit the existing profiles there
 		if ($global_directory != DI::config()->get('system', 'directory') && ($global_directory != '')) {
-			Config::set('system', 'directory', $global_directory);
+			DI::config()->set('system', 'directory', $global_directory);
 			Worker::add(PRIORITY_LOW, 'Directory');
 		}
 
@@ -278,129 +278,129 @@ class Site extends BaseAdminModule
 				);
 			}
 		}
-		Config::set('system', 'ssl_policy'            , $ssl_policy);
-		Config::set('system', 'maxloadavg'            , $maxloadavg);
-		Config::set('system', 'maxloadavg_frontend'   , $maxloadavg_frontend);
-		Config::set('system', 'min_memory'            , $min_memory);
-		Config::set('system', 'optimize_max_tablesize', $optimize_max_tablesize);
-		Config::set('system', 'optimize_fragmentation', $optimize_fragmentation);
-		Config::set('system', 'poco_completion'       , $poco_completion);
-		Config::set('system', 'poco_requery_days'     , $poco_requery_days);
-		Config::set('system', 'poco_discovery'        , $poco_discovery);
-		Config::set('system', 'poco_discovery_since'  , $poco_discovery_since);
-		Config::set('system', 'poco_local_search'     , $poco_local_search);
-		Config::set('system', 'nodeinfo'              , $nodeinfo);
-		Config::set('config', 'sitename'              , $sitename);
-		Config::set('config', 'sender_email'          , $sender_email);
-		Config::set('system', 'suppress_tags'         , $suppress_tags);
-		Config::set('system', 'shortcut_icon'         , $shortcut_icon);
-		Config::set('system', 'touch_icon'            , $touch_icon);
+		DI::config()->set('system', 'ssl_policy'            , $ssl_policy);
+		DI::config()->set('system', 'maxloadavg'            , $maxloadavg);
+		DI::config()->set('system', 'maxloadavg_frontend'   , $maxloadavg_frontend);
+		DI::config()->set('system', 'min_memory'            , $min_memory);
+		DI::config()->set('system', 'optimize_max_tablesize', $optimize_max_tablesize);
+		DI::config()->set('system', 'optimize_fragmentation', $optimize_fragmentation);
+		DI::config()->set('system', 'poco_completion'       , $poco_completion);
+		DI::config()->set('system', 'poco_requery_days'     , $poco_requery_days);
+		DI::config()->set('system', 'poco_discovery'        , $poco_discovery);
+		DI::config()->set('system', 'poco_discovery_since'  , $poco_discovery_since);
+		DI::config()->set('system', 'poco_local_search'     , $poco_local_search);
+		DI::config()->set('system', 'nodeinfo'              , $nodeinfo);
+		DI::config()->set('config', 'sitename'              , $sitename);
+		DI::config()->set('config', 'sender_email'          , $sender_email);
+		DI::config()->set('system', 'suppress_tags'         , $suppress_tags);
+		DI::config()->set('system', 'shortcut_icon'         , $shortcut_icon);
+		DI::config()->set('system', 'touch_icon'            , $touch_icon);
 
 		if ($banner == "") {
 			Config::delete('system', 'banner');
 		} else {
-			Config::set('system', 'banner', $banner);
+			DI::config()->set('system', 'banner', $banner);
 		}
 
 		if (empty($additional_info)) {
 			Config::delete('config', 'info');
 		} else {
-			Config::set('config', 'info', $additional_info);
+			DI::config()->set('config', 'info', $additional_info);
 		}
-		Config::set('system', 'language', $language);
-		Config::set('system', 'theme', $theme);
+		DI::config()->set('system', 'language', $language);
+		DI::config()->set('system', 'theme', $theme);
 		Theme::install($theme);
 
 		if ($theme_mobile == '---') {
 			Config::delete('system', 'mobile-theme');
 		} else {
-			Config::set('system', 'mobile-theme', $theme_mobile);
+			DI::config()->set('system', 'mobile-theme', $theme_mobile);
 		}
 		if ($singleuser == '---') {
 			Config::delete('system', 'singleuser');
 		} else {
-			Config::set('system', 'singleuser', $singleuser);
+			DI::config()->set('system', 'singleuser', $singleuser);
 		}
-		Config::set('system', 'maximagesize'           , $maximagesize);
-		Config::set('system', 'max_image_length'       , $maximagelength);
-		Config::set('system', 'jpeg_quality'           , $jpegimagequality);
+		DI::config()->set('system', 'maximagesize'           , $maximagesize);
+		DI::config()->set('system', 'max_image_length'       , $maximagelength);
+		DI::config()->set('system', 'jpeg_quality'           , $jpegimagequality);
 
-		Config::set('config', 'register_policy'        , $register_policy);
-		Config::set('system', 'max_daily_registrations', $daily_registrations);
-		Config::set('system', 'account_abandon_days'   , $abandon_days);
-		Config::set('config', 'register_text'          , $register_text);
-		Config::set('system', 'allowed_sites'          , $allowed_sites);
-		Config::set('system', 'allowed_email'          , $allowed_email);
-		Config::set('system', 'forbidden_nicknames'    , $forbidden_nicknames);
-		Config::set('system', 'no_oembed_rich_content' , $no_oembed_rich_content);
-		Config::set('system', 'allowed_oembed'         , $allowed_oembed);
-		Config::set('system', 'block_public'           , $block_public);
-		Config::set('system', 'publish_all'            , $force_publish);
-		Config::set('system', 'newuser_private'        , $newuser_private);
-		Config::set('system', 'enotify_no_content'     , $enotify_no_content);
-		Config::set('system', 'disable_embedded'       , $disable_embedded);
-		Config::set('system', 'allow_users_remote_self', $allow_users_remote_self);
-		Config::set('system', 'explicit_content'       , $explicit_content);
-		Config::set('system', 'check_new_version_url'  , $check_new_version_url);
+		DI::config()->set('config', 'register_policy'        , $register_policy);
+		DI::config()->set('system', 'max_daily_registrations', $daily_registrations);
+		DI::config()->set('system', 'account_abandon_days'   , $abandon_days);
+		DI::config()->set('config', 'register_text'          , $register_text);
+		DI::config()->set('system', 'allowed_sites'          , $allowed_sites);
+		DI::config()->set('system', 'allowed_email'          , $allowed_email);
+		DI::config()->set('system', 'forbidden_nicknames'    , $forbidden_nicknames);
+		DI::config()->set('system', 'no_oembed_rich_content' , $no_oembed_rich_content);
+		DI::config()->set('system', 'allowed_oembed'         , $allowed_oembed);
+		DI::config()->set('system', 'block_public'           , $block_public);
+		DI::config()->set('system', 'publish_all'            , $force_publish);
+		DI::config()->set('system', 'newuser_private'        , $newuser_private);
+		DI::config()->set('system', 'enotify_no_content'     , $enotify_no_content);
+		DI::config()->set('system', 'disable_embedded'       , $disable_embedded);
+		DI::config()->set('system', 'allow_users_remote_self', $allow_users_remote_self);
+		DI::config()->set('system', 'explicit_content'       , $explicit_content);
+		DI::config()->set('system', 'check_new_version_url'  , $check_new_version_url);
 
-		Config::set('system', 'block_extended_register', $no_multi_reg);
-		Config::set('system', 'no_openid'              , $no_openid);
-		Config::set('system', 'no_regfullname'         , $no_regfullname);
-		Config::set('system', 'community_page_style'   , $community_page_style);
-		Config::set('system', 'max_author_posts_community_page', $max_author_posts_community_page);
-		Config::set('system', 'verifyssl'              , $verifyssl);
-		Config::set('system', 'proxyuser'              , $proxyuser);
-		Config::set('system', 'proxy'                  , $proxy);
-		Config::set('system', 'curl_timeout'           , $timeout);
-		Config::set('system', 'dfrn_only'              , $dfrn_only);
-		Config::set('system', 'ostatus_disabled'       , $ostatus_disabled);
-		Config::set('system', 'diaspora_enabled'       , $diaspora_enabled);
+		DI::config()->set('system', 'block_extended_register', $no_multi_reg);
+		DI::config()->set('system', 'no_openid'              , $no_openid);
+		DI::config()->set('system', 'no_regfullname'         , $no_regfullname);
+		DI::config()->set('system', 'community_page_style'   , $community_page_style);
+		DI::config()->set('system', 'max_author_posts_community_page', $max_author_posts_community_page);
+		DI::config()->set('system', 'verifyssl'              , $verifyssl);
+		DI::config()->set('system', 'proxyuser'              , $proxyuser);
+		DI::config()->set('system', 'proxy'                  , $proxy);
+		DI::config()->set('system', 'curl_timeout'           , $timeout);
+		DI::config()->set('system', 'dfrn_only'              , $dfrn_only);
+		DI::config()->set('system', 'ostatus_disabled'       , $ostatus_disabled);
+		DI::config()->set('system', 'diaspora_enabled'       , $diaspora_enabled);
 
-		Config::set('config', 'private_addons'         , $private_addons);
+		DI::config()->set('config', 'private_addons'         , $private_addons);
 
-		Config::set('system', 'force_ssl'              , $force_ssl);
-		Config::set('system', 'hide_help'              , $hide_help);
+		DI::config()->set('system', 'force_ssl'              , $force_ssl);
+		DI::config()->set('system', 'hide_help'              , $hide_help);
 
-		Config::set('system', 'dbclean'                , $dbclean);
-		Config::set('system', 'dbclean-expire-days'    , $dbclean_expire_days);
-		Config::set('system', 'dbclean_expire_conversation', $dbclean_expire_conv);
+		DI::config()->set('system', 'dbclean'                , $dbclean);
+		DI::config()->set('system', 'dbclean-expire-days'    , $dbclean_expire_days);
+		DI::config()->set('system', 'dbclean_expire_conversation', $dbclean_expire_conv);
 
 		if ($dbclean_unclaimed == 0) {
 			$dbclean_unclaimed = $dbclean_expire_days;
 		}
 
-		Config::set('system', 'dbclean-expire-unclaimed', $dbclean_unclaimed);
+		DI::config()->set('system', 'dbclean-expire-unclaimed', $dbclean_unclaimed);
 
 		if ($itemcache != '') {
 			$itemcache = BasePath::getRealPath($itemcache);
 		}
 
-		Config::set('system', 'itemcache', $itemcache);
-		Config::set('system', 'itemcache_duration', $itemcache_duration);
-		Config::set('system', 'max_comments', $max_comments);
+		DI::config()->set('system', 'itemcache', $itemcache);
+		DI::config()->set('system', 'itemcache_duration', $itemcache_duration);
+		DI::config()->set('system', 'max_comments', $max_comments);
 
 		if ($temppath != '') {
 			$temppath = BasePath::getRealPath($temppath);
 		}
 
-		Config::set('system', 'temppath', $temppath);
+		DI::config()->set('system', 'temppath', $temppath);
 
-		Config::set('system', 'proxy_disabled'   , $proxy_disabled);
-		Config::set('system', 'only_tag_search'  , $only_tag_search);
+		DI::config()->set('system', 'proxy_disabled'   , $proxy_disabled);
+		DI::config()->set('system', 'only_tag_search'  , $only_tag_search);
 
-		Config::set('system', 'worker_queues'    , $worker_queues);
-		Config::set('system', 'worker_dont_fork' , $worker_dont_fork);
-		Config::set('system', 'worker_fastlane'  , $worker_fastlane);
-		Config::set('system', 'frontend_worker'  , $worker_frontend);
+		DI::config()->set('system', 'worker_queues'    , $worker_queues);
+		DI::config()->set('system', 'worker_dont_fork' , $worker_dont_fork);
+		DI::config()->set('system', 'worker_fastlane'  , $worker_fastlane);
+		DI::config()->set('system', 'frontend_worker'  , $worker_frontend);
 
-		Config::set('system', 'relay_directly'   , $relay_directly);
-		Config::set('system', 'relay_server'     , $relay_server);
-		Config::set('system', 'relay_subscribe'  , $relay_subscribe);
-		Config::set('system', 'relay_scope'      , $relay_scope);
-		Config::set('system', 'relay_server_tags', $relay_server_tags);
-		Config::set('system', 'relay_user_tags'  , $relay_user_tags);
+		DI::config()->set('system', 'relay_directly'   , $relay_directly);
+		DI::config()->set('system', 'relay_server'     , $relay_server);
+		DI::config()->set('system', 'relay_subscribe'  , $relay_subscribe);
+		DI::config()->set('system', 'relay_scope'      , $relay_scope);
+		DI::config()->set('system', 'relay_server_tags', $relay_server_tags);
+		DI::config()->set('system', 'relay_user_tags'  , $relay_user_tags);
 
-		Config::set('system', 'rino_encrypt'     , $rino);
+		DI::config()->set('system', 'rino_encrypt'     , $rino);
 
 		info(DI::l10n()->t('Site settings updated.') . EOL);
 
@@ -416,7 +416,7 @@ class Site extends BaseAdminModule
 
 		if (strlen(DI::config()->get('system', 'directory_submit_url')) &&
 			!strlen(DI::config()->get('system', 'directory'))) {
-			Config::set('system', 'directory', dirname(DI::config()->get('system', 'directory_submit_url')));
+			DI::config()->set('system', 'directory', dirname(DI::config()->get('system', 'directory_submit_url')));
 			Config::delete('system', 'directory_submit_url');
 		}
 
diff --git a/src/Module/Admin/Summary.php b/src/Module/Admin/Summary.php
index a8b037d5d3..c74f877268 100644
--- a/src/Module/Admin/Summary.php
+++ b/src/Module/Admin/Summary.php
@@ -115,7 +115,7 @@ class Summary extends BaseAdminModule
 		$confBasepath = $configCache->get('system', 'basepath');
 		$currBasepath = DI::config()->get('system', 'basepath');
 		if ($confBasepath !== $currBasepath || !is_dir($currBasepath)) {
-			if (is_dir($confBasepath) && Config::set('system', 'basepath', $confBasepath)) {
+			if (is_dir($confBasepath) && DI::config()->set('system', 'basepath', $confBasepath)) {
 				DI::logger()->info('Friendica\'s system.basepath was updated successfully.', [
 					'from' => $currBasepath,
 					'to'   => $confBasepath,
diff --git a/src/Module/Admin/Tos.php b/src/Module/Admin/Tos.php
index 000dedd051..aa819fe41a 100644
--- a/src/Module/Admin/Tos.php
+++ b/src/Module/Admin/Tos.php
@@ -23,9 +23,9 @@ class Tos extends BaseAdminModule
 		$displayprivstatement = !empty($_POST['displayprivstatement']);
 		$tostext = (!empty($_POST['tostext']) ? strip_tags(trim($_POST['tostext'])) : '');
 
-		Config::set('system', 'tosdisplay', $displaytos);
-		Config::set('system', 'tosprivstatement', $displayprivstatement);
-		Config::set('system', 'tostext', $tostext);
+		DI::config()->set('system', 'tosdisplay', $displaytos);
+		DI::config()->set('system', 'tosprivstatement', $displayprivstatement);
+		DI::config()->set('system', 'tostext', $tostext);
 
 		info(DI::l10n()->t('The Terms of Service settings have been updated.'));
 
diff --git a/src/Protocol/DFRN.php b/src/Protocol/DFRN.php
index 00e0df5f42..fe362839f3 100644
--- a/src/Protocol/DFRN.php
+++ b/src/Protocol/DFRN.php
@@ -492,8 +492,8 @@ class DFRN
 		$pubkey = DI::config()->get('system', 'site_pubkey');
 		if (! $pubkey) {
 			$res = Crypto::newKeypair(1024);
-			Config::set('system', 'site_prvkey', $res['prvkey']);
-			Config::set('system', 'site_pubkey', $res['pubkey']);
+			DI::config()->set('system', 'site_prvkey', $res['prvkey']);
+			DI::config()->set('system', 'site_pubkey', $res['pubkey']);
 		}
 
 		$rp = q(
diff --git a/src/Worker/CheckVersion.php b/src/Worker/CheckVersion.php
index b6fdd7f026..a25651523c 100644
--- a/src/Worker/CheckVersion.php
+++ b/src/Worker/CheckVersion.php
@@ -43,7 +43,7 @@ class CheckVersion
 		$gitversion = DBA::escape(trim(Network::fetchUrl($checked_url)));
 		Logger::log("Upstream VERSION is: ".$gitversion, Logger::DEBUG);
 
-		Config::set('system', 'git_friendica_version', $gitversion);
+		DI::config()->set('system', 'git_friendica_version', $gitversion);
 
 		Logger::log('checkversion: end');
 
diff --git a/src/Worker/Cron.php b/src/Worker/Cron.php
index 7a59d64ffb..559085be24 100644
--- a/src/Worker/Cron.php
+++ b/src/Worker/Cron.php
@@ -86,7 +86,7 @@ class Cron
 
 			self::checkdeletedContacts();
 
-			Config::set('system', 'last_expire_day', $d2);
+			DI::config()->set('system', 'last_expire_day', $d2);
 		}
 
 		// Hourly cron calls
@@ -100,7 +100,7 @@ class Cron
 				DBA::e("OPTIMIZE TABLE `workerqueue`");
 			}
 
-			Config::set('system', 'last_cron_hourly', time());
+			DI::config()->set('system', 'last_cron_hourly', time());
 		}
 
 		// Ensure to have a .htaccess file.
@@ -118,7 +118,7 @@ class Cron
 
 		Logger::log('cron: end');
 
-		Config::set('system', 'last_cron', time());
+		DI::config()->set('system', 'last_cron', time());
 
 		return;
 	}
diff --git a/src/Worker/CronJobs.php b/src/Worker/CronJobs.php
index 5487b35d67..48b4923c76 100644
--- a/src/Worker/CronJobs.php
+++ b/src/Worker/CronJobs.php
@@ -226,7 +226,7 @@ class CronJobs
 			}
 		}
 
-		Config::set('system', 'cache_last_cleared', time());
+		DI::config()->set('system', 'cache_last_cleared', time());
 	}
 
 	/**
diff --git a/src/Worker/DBClean.php b/src/Worker/DBClean.php
index 11e73c24a2..60f0e64c42 100644
--- a/src/Worker/DBClean.php
+++ b/src/Worker/DBClean.php
@@ -98,7 +98,7 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." old global item entries from item table without user copy. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-1', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-1', $last_id);
 		} elseif ($stage == 2) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-2', 0);
 
@@ -120,10 +120,10 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." items without parents. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-2', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-2', $last_id);
 
 			if ($count < $limit) {
-				Config::set('system', 'finished-dbclean-2', true);
+				DI::config()->set('system', 'finished-dbclean-2', true);
 			}
 		} elseif ($stage == 3) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-3', 0);
@@ -146,10 +146,10 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." orphaned data from thread table. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-3', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-3', $last_id);
 
 			if ($count < $limit) {
-				Config::set('system', 'finished-dbclean-3', true);
+				DI::config()->set('system', 'finished-dbclean-3', true);
 			}
 		} elseif ($stage == 4) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-4', 0);
@@ -172,10 +172,10 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." orphaned data from notify table. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-4', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-4', $last_id);
 
 			if ($count < $limit) {
-				Config::set('system', 'finished-dbclean-4', true);
+				DI::config()->set('system', 'finished-dbclean-4', true);
 			}
 		} elseif ($stage == 5) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-5', 0);
@@ -198,10 +198,10 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." orphaned data from notify-threads table. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-5', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-5', $last_id);
 
 			if ($count < $limit) {
-				Config::set('system', 'finished-dbclean-5', true);
+				DI::config()->set('system', 'finished-dbclean-5', true);
 			}
 		} elseif ($stage == 6) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-6', 0);
@@ -224,10 +224,10 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." orphaned data from sign table. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-6', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-6', $last_id);
 
 			if ($count < $limit) {
-				Config::set('system', 'finished-dbclean-6', true);
+				DI::config()->set('system', 'finished-dbclean-6', true);
 			}
 		} elseif ($stage == 7) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-7', 0);
@@ -250,10 +250,10 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." orphaned data from term table. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-7', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-7', $last_id);
 
 			if ($count < $limit) {
-				Config::set('system', 'finished-dbclean-7', true);
+				DI::config()->set('system', 'finished-dbclean-7', true);
 			}
 		} elseif ($stage == 8) {
 			if ($days <= 0) {
@@ -289,7 +289,7 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." expired threads. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-8', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-8', $last_id);
 		} elseif ($stage == 9) {
 			if ($days <= 0) {
 				return;
@@ -317,7 +317,7 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." old global item entries from expired threads. Last ID: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-9', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-9', $last_id);
 		} elseif ($stage == 10) {
 			$last_id = DI::config()->get('system', 'dbclean-last-id-10', 0);
 			$days = intval(DI::config()->get('system', 'dbclean_expire_conversation', 90));
@@ -340,7 +340,7 @@ class DBClean {
 			DBA::close($r);
 			Logger::log("Done deleting ".$count." conversations. Last created: ".$last_id);
 
-			Config::set('system', 'dbclean-last-id-10', $last_id);
+			DI::config()->set('system', 'dbclean-last-id-10', $last_id);
 		}
 	}
 }
diff --git a/tests/src/Database/DBATest.php b/tests/src/Database/DBATest.php
index 15d438b679..60008d0db0 100644
--- a/tests/src/Database/DBATest.php
+++ b/tests/src/Database/DBATest.php
@@ -21,11 +21,11 @@ class DBATest extends DatabaseTest
 		DI::init($dice);
 
 		// Default config
-		Config::set('config', 'hostname', 'localhost');
-		Config::set('system', 'throttle_limit_day', 100);
-		Config::set('system', 'throttle_limit_week', 100);
-		Config::set('system', 'throttle_limit_month', 100);
-		Config::set('system', 'theme', 'system_theme');
+		DI::config()->set('config', 'hostname', 'localhost');
+		DI::config()->set('system', 'throttle_limit_day', 100);
+		DI::config()->set('system', 'throttle_limit_week', 100);
+		DI::config()->set('system', 'throttle_limit_month', 100);
+		DI::config()->set('system', 'theme', 'system_theme');
 	}
 
 	/**
diff --git a/update.php b/update.php
index d8591ec523..a40d19785c 100644
--- a/update.php
+++ b/update.php
@@ -65,7 +65,7 @@ function update_1178()
 function update_1179()
 {
 	if (DI::config()->get('system', 'no_community_page')) {
-		Config::set('system', 'community_page_style', CP_NO_COMMUNITY_PAGE);
+		DI::config()->set('system', 'community_page_style', CP_NO_COMMUNITY_PAGE);
 	}
 
 	// Update the central item storage with uid=0
@@ -88,7 +88,7 @@ function update_1189()
 
 	if (strlen(DI::config()->get('system', 'directory_submit_url')) &&
 		!strlen(DI::config()->get('system', 'directory'))) {
-		Config::set('system', 'directory', dirname(DI::config()->get('system', 'directory_submit_url')));
+		DI::config()->set('system', 'directory', dirname(DI::config()->get('system', 'directory_submit_url')));
 		Config::delete('system', 'directory_submit_url');
 	}
 
@@ -97,7 +97,7 @@ function update_1189()
 
 function update_1191()
 {
-	Config::set('system', 'maintenance', 1);
+	DI::config()->set('system', 'maintenance', 1);
 
 	if (Addon::isEnabled('forumlist')) {
 		$addon = 'forumlist';
@@ -114,7 +114,7 @@ function update_1191()
 				// since Addon::uninstall() don't work here
 				q("DELETE FROM `addon` WHERE `name` = 'forumlist' ");
 				q("DELETE FROM `hook` WHERE `file` = 'addon/forumlist/forumlist.php' ");
-				Config::set('system', 'addon', implode(", ", $addons_arr));
+				DI::config()->set('system', 'addon', implode(", ", $addons_arr));
 			}
 		}
 	}
@@ -154,7 +154,7 @@ function update_1191()
 		}
 	}
 
-	Config::set('system', 'maintenance', 0);
+	DI::config()->set('system', 'maintenance', 0);
 
 	return Update::SUCCESS;
 }
@@ -193,7 +193,7 @@ function update_1245()
 		return Update::SUCCESS;
 	}
 
-	Config::set('system', 'rino_encrypt', 1);
+	DI::config()->set('system', 'rino_encrypt', 1);
 
 	return Update::SUCCESS;
 }
@@ -210,8 +210,8 @@ WHERE `hook` LIKE 'plugin_%'");
 
 function update_1260()
 {
-	Config::set('system', 'maintenance', 1);
-	Config::set(
+	DI::config()->set('system', 'maintenance', 1);
+	DI::config()->set(
 		'system',
 		'maintenance_reason',
 		DI::l10n()->t(
@@ -252,7 +252,7 @@ function update_1260()
 	DBA::e("UPDATE `thread` INNER JOIN `item` ON `thread`.`iid` = `item`.`id`
 		SET `thread`.`author-id` = `item`.`author-id` WHERE `thread`.`author-id` = 0");
 
-	Config::set('system', 'maintenance', 0);
+	DI::config()->set('system', 'maintenance', 0);
 	return Update::SUCCESS;
 }
 
@@ -265,8 +265,8 @@ function update_1261()
 
 function update_1278()
 {
-	Config::set('system', 'maintenance', 1);
-	Config::set(
+	DI::config()->set('system', 'maintenance', 1);
+	DI::config()->set(
 		'system',
 		'maintenance_reason',
 		DI::l10n()->t(
@@ -278,7 +278,7 @@ function update_1278()
 	Item::update(['post-type' => Item::PT_PAGE], ['bookmark' => true]);
 	Item::update(['post-type' => Item::PT_PERSONAL_NOTE], ['type' => 'note']);
 
-	Config::set('system', 'maintenance', 0);
+	DI::config()->set('system', 'maintenance', 0);
 
 	return Update::SUCCESS;
 }
@@ -415,7 +415,7 @@ function update_1330()
 	// set the name of the storage instead of the classpath as config
 	if (!empty($currStorage)) {
 		/** @var Storage\IStorage $currStorage */
-		if (!Config::set('storage', 'name', $currStorage::getName())) {
+		if (!DI::config()->set('storage', 'name', $currStorage::getName())) {
 			return Update::FAILED;
 		}
 
diff --git a/view/theme/duepuntozero/config.php b/view/theme/duepuntozero/config.php
index 5629d95c49..652cea9574 100644
--- a/view/theme/duepuntozero/config.php
+++ b/view/theme/duepuntozero/config.php
@@ -42,7 +42,7 @@ function theme_admin(App $a)
 function theme_admin_post(App $a)
 {
 	if (isset($_POST['duepuntozero-settings-submit'])) {
-		Config::set('duepuntozero', 'colorset', $_POST['duepuntozero_colorset']);
+		DI::config()->set('duepuntozero', 'colorset', $_POST['duepuntozero_colorset']);
 	}
 }
 
diff --git a/view/theme/frio/config.php b/view/theme/frio/config.php
index 95d9a0e4ec..2e76ae261c 100644
--- a/view/theme/frio/config.php
+++ b/view/theme/frio/config.php
@@ -34,18 +34,18 @@ function theme_admin_post(App $a)
 	}
 
 	if (isset($_POST['frio-settings-submit'])) {
-		Config::set('frio', 'scheme',           $_POST['frio_scheme']           ?? '');
-		Config::set('frio', 'nav_bg',           $_POST['frio_nav_bg']           ?? '');
-		Config::set('frio', 'nav_icon_color',   $_POST['frio_nav_icon_color']   ?? '');
-		Config::set('frio', 'link_color',       $_POST['frio_link_color']       ?? '');
-		Config::set('frio', 'background_color', $_POST['frio_background_color'] ?? '');
-		Config::set('frio', 'contentbg_transp', $_POST['frio_contentbg_transp'] ?? '');
-		Config::set('frio', 'background_image', $_POST['frio_background_image'] ?? '');
-		Config::set('frio', 'bg_image_option',  $_POST['frio_bg_image_option']  ?? '');
-		Config::set('frio', 'login_bg_image',   $_POST['frio_login_bg_image']   ?? '');
-		Config::set('frio', 'login_bg_color',   $_POST['frio_login_bg_color']   ?? '');
-		Config::set('frio', 'css_modified',     time());
-		Config::set('frio', 'enable_compose',   $_POST['frio_enable_compose']   ?? 0);
+		DI::config()->set('frio', 'scheme',           $_POST['frio_scheme']           ?? '');
+		DI::config()->set('frio', 'nav_bg',           $_POST['frio_nav_bg']           ?? '');
+		DI::config()->set('frio', 'nav_icon_color',   $_POST['frio_nav_icon_color']   ?? '');
+		DI::config()->set('frio', 'link_color',       $_POST['frio_link_color']       ?? '');
+		DI::config()->set('frio', 'background_color', $_POST['frio_background_color'] ?? '');
+		DI::config()->set('frio', 'contentbg_transp', $_POST['frio_contentbg_transp'] ?? '');
+		DI::config()->set('frio', 'background_image', $_POST['frio_background_image'] ?? '');
+		DI::config()->set('frio', 'bg_image_option',  $_POST['frio_bg_image_option']  ?? '');
+		DI::config()->set('frio', 'login_bg_image',   $_POST['frio_login_bg_image']   ?? '');
+		DI::config()->set('frio', 'login_bg_color',   $_POST['frio_login_bg_color']   ?? '');
+		DI::config()->set('frio', 'css_modified',     time());
+		DI::config()->set('frio', 'enable_compose',   $_POST['frio_enable_compose']   ?? 0);
 	}
 }
 
diff --git a/view/theme/quattro/config.php b/view/theme/quattro/config.php
index 51915cfd7c..459a0d7f40 100644
--- a/view/theme/quattro/config.php
+++ b/view/theme/quattro/config.php
@@ -45,10 +45,10 @@ function theme_admin(App $a) {
 
 function theme_admin_post(App $a) {
 	if (isset($_POST['quattro-settings-submit'])){
-		Config::set('quattro', 'align', $_POST['quattro_align']);
-		Config::set('quattro', 'color', $_POST['quattro_color']);
-		Config::set('quattro', 'tfs', $_POST['quattro_tfs']);
-		Config::set('quattro', 'pfs', $_POST['quattro_pfs']);
+		DI::config()->set('quattro', 'align', $_POST['quattro_align']);
+		DI::config()->set('quattro', 'color', $_POST['quattro_color']);
+		DI::config()->set('quattro', 'tfs', $_POST['quattro_tfs']);
+		DI::config()->set('quattro', 'pfs', $_POST['quattro_pfs']);
 	}
 }
 
diff --git a/view/theme/vier/config.php b/view/theme/vier/config.php
index 60c33975e2..2d185be2c8 100644
--- a/view/theme/vier/config.php
+++ b/view/theme/vier/config.php
@@ -90,14 +90,14 @@ function theme_admin(App $a) {
 
 function theme_admin_post(App $a) {
 	if (isset($_POST['vier-settings-submit'])){
-		Config::set('vier', 'style', $_POST['vier_style']);
-		Config::set('vier', 'show_pages', $_POST['vier_show_pages']);
-		Config::set('vier', 'show_profiles', $_POST['vier_show_profiles']);
-		Config::set('vier', 'show_helpers', $_POST['vier_show_helpers']);
-		Config::set('vier', 'show_services', $_POST['vier_show_services']);
-		Config::set('vier', 'show_friends', $_POST['vier_show_friends']);
-		Config::set('vier', 'show_lastusers', $_POST['vier_show_lastusers']);
-		Config::set('vier', 'helperlist', $_POST['vier_helperlist']);
+		DI::config()->set('vier', 'style', $_POST['vier_style']);
+		DI::config()->set('vier', 'show_pages', $_POST['vier_show_pages']);
+		DI::config()->set('vier', 'show_profiles', $_POST['vier_show_profiles']);
+		DI::config()->set('vier', 'show_helpers', $_POST['vier_show_helpers']);
+		DI::config()->set('vier', 'show_services', $_POST['vier_show_services']);
+		DI::config()->set('vier', 'show_friends', $_POST['vier_show_friends']);
+		DI::config()->set('vier', 'show_lastusers', $_POST['vier_show_lastusers']);
+		DI::config()->set('vier', 'helperlist', $_POST['vier_helperlist']);
 	}
 }