diff --git a/include/text.php b/include/text.php
index 5e189d58f1..52b51bdb0c 100644
--- a/include/text.php
+++ b/include/text.php
@@ -513,7 +513,7 @@ function load_view_file($s) {
 		return $content;
 	}
 
-	$theme = current_theme();
+	$theme = $a->getCurrentTheme();
 
 	if (file_exists("$d/theme/$theme/$b")) {
 		$stamp1 = microtime(true);
diff --git a/index.php b/index.php
index 2f23ea791a..b7ae6f1d4a 100644
--- a/index.php
+++ b/index.php
@@ -330,7 +330,7 @@ if (strlen($a->module)) {
 /**
  * Load current theme info
  */
-$theme_info_file = "view/theme/".current_theme()."/theme.php";
+$theme_info_file = 'view/theme/' . $a->getCurrentTheme() . '/theme.php';
 if (file_exists($theme_info_file)) {
 	require_once $theme_info_file;
 }
@@ -363,8 +363,8 @@ if ($a->module_loaded) {
 		$func($a);
 	}
 
-	if (function_exists(str_replace('-', '_', current_theme()) . '_init')) {
-		$func = str_replace('-', '_', current_theme()) . '_init';
+	if (function_exists(str_replace('-', '_', $a->getCurrentTheme()) . '_init')) {
+		$func = str_replace('-', '_', $a->getCurrentTheme()) . '_init';
 		$func($a);
 	}
 
@@ -402,8 +402,8 @@ if ($a->module_loaded) {
 		$a->page['content'] .= $arr['content'];
 	}
 
-	if (function_exists(str_replace('-', '_', current_theme()) . '_content_loaded')) {
-		$func = str_replace('-', '_', current_theme()) . '_content_loaded';
+	if (function_exists(str_replace('-', '_', $a->getCurrentTheme()) . '_content_loaded')) {
+		$func = str_replace('-', '_', $a->getCurrentTheme()) . '_content_loaded';
 		$func($a);
 	}
 }
@@ -478,7 +478,7 @@ if ($a->is_mobile || $a->is_tablet) {
  */
 
 if (!$a->theme['stylesheet']) {
-	$stylesheet = current_theme_url();
+	$stylesheet = $a->getCurrentThemeStylesheetPath();
 } else {
 	$stylesheet = $a->theme['stylesheet'];
 }
diff --git a/src/Core/Addon.php b/src/Core/Addon.php
index 3adc7fc0ec..50247d240f 100644
--- a/src/Core/Addon.php
+++ b/src/Core/Addon.php
@@ -228,14 +228,15 @@ class Addon
 	/**
 	 * @brief Calls a single hook.
 	 *
-	 * @param string $name of the hook to call
-	 * @param array $hook Hook data
-	 * @param string|array &$data to transmit to the callback handler
+	 * @param \Friendica\App $a
+	 * @param string         $name of the hook to call
+	 * @param array          $hook Hook data
+	 * @param string|array   &$data to transmit to the callback handler
 	 */
-	public static function callSingleHook($a, $name, $hook, &$data = null)
+	public static function callSingleHook(\Friendica\App $a, $name, $hook, &$data = null)
 	{
 		// Don't run a theme's hook if the user isn't using the theme
-		if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/'.current_theme()) === false) {
+		if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/' . $a->getCurrentTheme()) === false) {
 			return;
 		}
 
diff --git a/src/Core/Theme.php b/src/Core/Theme.php
index fe38d09ede..c64ed08d3b 100644
--- a/src/Core/Theme.php
+++ b/src/Core/Theme.php
@@ -162,7 +162,7 @@ class Theme
 		} else {
 			$parent = 'NOPATH';
 		}
-		$theme = current_theme();
+		$theme = get_app()->getCurrentTheme();
 		$thname = $theme;
 		$ext = substr($file, strrpos($file, '.') + 1);
 		$paths = [
diff --git a/src/Model/Profile.php b/src/Model/Profile.php
index d4773a8062..8bb519448e 100644
--- a/src/Model/Profile.php
+++ b/src/Model/Profile.php
@@ -152,7 +152,7 @@ class Profile
 
 		$a->set_template_engine(); // reset the template engine to the default in case the user's theme doesn't specify one
 
-		$theme_info_file = 'view/theme/' . current_theme() . '/theme.php';
+		$theme_info_file = 'view/theme/' . $a->getCurrentTheme() . '/theme.php';
 		if (file_exists($theme_info_file)) {
 			require_once $theme_info_file;
 		}
diff --git a/src/Render/FriendicaSmarty.php b/src/Render/FriendicaSmarty.php
index ab19993081..8c8e637630 100644
--- a/src/Render/FriendicaSmarty.php
+++ b/src/Render/FriendicaSmarty.php
@@ -22,7 +22,7 @@ class FriendicaSmarty extends Smarty
 		parent::__construct();
 
 		$a = get_app();
-		$theme = current_theme();
+		$theme = $a->getCurrentTheme();
 
 		// setTemplateDir can be set to an array, which Smarty will parse in order.
 		// The order is thus very important here
diff --git a/src/Render/FriendicaSmartyEngine.php b/src/Render/FriendicaSmartyEngine.php
index 949ac58c82..c6e95ee068 100644
--- a/src/Render/FriendicaSmartyEngine.php
+++ b/src/Render/FriendicaSmartyEngine.php
@@ -62,7 +62,7 @@ class FriendicaSmartyEngine implements ITemplateEngine
 			$root = $root . '/';
 		}
 
-		$theme = current_theme();
+		$theme = $a->getCurrentTheme();
 		$filename = $template::SMARTY3_TEMPLATE_FOLDER . '/' . $file;
 
 		if (file_exists("{$root}view/theme/$theme/$filename")) {
diff --git a/view/theme/frio/php/frio_boot.php b/view/theme/frio/php/frio_boot.php
index 243ea5c72c..3f8ed1ed0b 100644
--- a/view/theme/frio/php/frio_boot.php
+++ b/view/theme/frio/php/frio_boot.php
@@ -21,12 +21,12 @@ function load_page(App $a)
 	} elseif ((isset($_GET['mode']) && ($_GET['mode'] == 'none'))) {
 		require 'view/theme/frio/none.php';
 	} else {
-		$template = 'view/theme/' . current_theme() . '/'
+		$template = 'view/theme/' . $a->getCurrentTheme() . '/'
 			. ((x($a->page, 'template')) ? $a->page['template'] : 'default' ) . '.php';
 		if (file_exists($template)) {
 			require_once $template;
 		} else {
-			require_once str_replace('theme/' . current_theme() . '/', '', $template);
+			require_once str_replace('theme/' . $a->getCurrentTheme() . '/', '', $template);
 		}
 	}
 }
diff --git a/view/theme/frio/php/scheme.php b/view/theme/frio/php/scheme.php
index 02de0a0359..538839b2c2 100644
--- a/view/theme/frio/php/scheme.php
+++ b/view/theme/frio/php/scheme.php
@@ -19,9 +19,11 @@
  */
 use Friendica\Core\PConfig;
 
+require_once 'boot.php';
+
 function get_scheme_info($scheme)
 {
-	$theme = current_theme();
+	$theme = get_app()->getCurrentTheme();
 	$themepath = 'view/theme/' . $theme . '/';
 	$scheme = PConfig::get(local_user(), 'frio', 'scheme', PConfig::get(local_user(), 'frio', 'scheme'));