diff --git a/include/security.php b/include/security.php
index af18a281a6..141738e4bc 100644
--- a/include/security.php
+++ b/include/security.php
@@ -179,7 +179,7 @@ function authenticate_success($user_record, $login_initial = false, $interactive
 		 * The cookie will be renewed automatically.
 		 * The week ensures that sessions will expire after some inactivity.
 		 */
-		if ($_SESSION['remember']) {
+		if (!empty($_SESSION['remember'])) {
 			logger('Injecting cookie for remembered user ' . $a->user['nickname']);
 			new_cookie(604800, $user_record);
 			unset($_SESSION['remember']);
@@ -225,7 +225,7 @@ function can_write_wall($owner)
 		} else {
 			$cid = 0;
 
-			if (is_array($_SESSION['remote'])) {
+			if (!empty($_SESSION['remote'])) {
 				foreach ($_SESSION['remote'] as $visitor) {
 					if ($visitor['uid'] == $owner) {
 						$cid = $visitor['cid'];
diff --git a/index.php b/index.php
index b33db80b69..8d40dbf85f 100644
--- a/index.php
+++ b/index.php
@@ -100,7 +100,7 @@ if (x($_SESSION, 'authenticated') && !x($_SESSION, 'language')) {
 	}
 }
 
-if ((x($_SESSION, 'language')) && ($_SESSION['language'] !== $lang)) {
+if (x($_SESSION, 'language') && ($_SESSION['language'] !== $lang)) {
 	$lang = $_SESSION['language'];
 	L10n::loadTranslationTable($lang);
 }
diff --git a/mod/cal.php b/mod/cal.php
index 7796a459d0..5779b0316a 100644
--- a/mod/cal.php
+++ b/mod/cal.php
@@ -28,52 +28,54 @@ function cal_init(App $a)
 		DFRN::autoRedir($a, $a->argv[1]);
 	}
 
-	if ((Config::get('system', 'block_public')) && (!local_user()) && (!remote_user())) {
+	if (Config::get('system', 'block_public') && !local_user() && !remote_user()) {
 		return;
 	}
 
+	if ($a->argc < 2) {
+		System::httpExit(403, ["title" => L10n::t('Access denied.')]);
+	}
+
 	Nav::setSelected('events');
 
-	if ($a->argc > 1) {
-		$nick = $a->argv[1];
-		$user = DBA::selectFirst('user', [], ['nickname' => $nick, 'blocked' => false]);
-		if (!DBA::isResult($user)) {
-			return;
-		}
-
-		$a->data['user'] = $user;
-		$a->profile_uid = $user['uid'];
-
-		// if it's a json request abort here becaus we don't
-		// need the widget data
-		if (!empty($a->argv[2]) && ($a->argv[2] === 'json')) {
-			return;
-		}
-
-		$profile = Profile::getByNickname($nick, $a->profile_uid);
-
-		$account_type = Contact::getAccountType($profile);
-
-		$tpl = get_markup_template("vcard-widget.tpl");
-
-		$vcard_widget = replace_macros($tpl, [
-			'$name' => $profile['name'],
-			'$photo' => $profile['photo'],
-			'$addr' => (($profile['addr'] != "") ? $profile['addr'] : ""),
-			'$account_type' => $account_type,
-			'$pdesc' => (($profile['pdesc'] != "") ? $profile['pdesc'] : ""),
-		]);
-
-		$cal_widget = Widget\CalendarExport::getHTML();
-
-		if (!x($a->page, 'aside')) {
-			$a->page['aside'] = '';
-		}
-
-		$a->page['aside'] .= $vcard_widget;
-		$a->page['aside'] .= $cal_widget;
+	$nick = $a->argv[1];
+	$user = DBA::selectFirst('user', [], ['nickname' => $nick, 'blocked' => false]);
+	if (!DBA::isResult($user)) {
+		return;
 	}
 
+	$a->data['user'] = $user;
+	$a->profile_uid = $user['uid'];
+
+	// if it's a json request abort here becaus we don't
+	// need the widget data
+	if (!empty($a->argv[2]) && ($a->argv[2] === 'json')) {
+		return;
+	}
+
+	$profile = Profile::getByNickname($nick, $a->profile_uid);
+
+	$account_type = Contact::getAccountType($profile);
+
+	$tpl = get_markup_template("vcard-widget.tpl");
+
+	$vcard_widget = replace_macros($tpl, [
+		'$name' => $profile['name'],
+		'$photo' => $profile['photo'],
+		'$addr' => (($profile['addr'] != "") ? $profile['addr'] : ""),
+		'$account_type' => $account_type,
+		'$pdesc' => (($profile['pdesc'] != "") ? $profile['pdesc'] : ""),
+	]);
+
+	$cal_widget = Widget\CalendarExport::getHTML();
+
+	if (!x($a->page, 'aside')) {
+		$a->page['aside'] = '';
+	}
+
+	$a->page['aside'] .= $vcard_widget;
+	$a->page['aside'] .= $cal_widget;
+
 	return;
 }
 
@@ -100,7 +102,7 @@ function cal_content(App $a)
 	$mode = 'view';
 	$y = 0;
 	$m = 0;
-	$ignored = ((x($_REQUEST, 'ignored')) ? intval($_REQUEST['ignored']) : 0);
+	$ignored = (x($_REQUEST, 'ignored') ? intval($_REQUEST['ignored']) : 0);
 
 	$format = 'ical';
 	if ($a->argc == 4 && $a->argv[2] == 'export') {
@@ -138,7 +140,7 @@ function cal_content(App $a)
 
 	$is_owner = local_user() == $a->profile['profile_uid'];
 
-	if ($a->profile['hidewall'] && (!$is_owner) && (!$remote_contact)) {
+	if ($a->profile['hidewall'] && !$is_owner && !$remote_contact) {
 		notice(L10n::t('Access to this profile has been restricted.') . EOL);
 		return;
 	}
@@ -293,14 +295,14 @@ function cal_content(App $a)
 	}
 
 	if ($mode == 'export') {
-		if (!(intval($owner_uid))) {
+		if (!intval($owner_uid)) {
 			notice(L10n::t('User not found'));
 			return;
 		}
 
 		// Test permissions
 		// Respect the export feature setting for all other /cal pages if it's not the own profile
-		if (((local_user() !== intval($owner_uid))) && !Feature::isEnabled($owner_uid, "export_calendar")) {
+		if ((local_user() !== intval($owner_uid)) && !Feature::isEnabled($owner_uid, "export_calendar")) {
 			notice(L10n::t('Permission denied.') . EOL);
 			goaway('cal/' . $nick);
 		}
diff --git a/mod/manage.php b/mod/manage.php
index 457b0eede4..f81afb09a6 100644
--- a/mod/manage.php
+++ b/mod/manage.php
@@ -132,7 +132,7 @@ function manage_content(App $a) {
 		return;
 	}
 
-	if ($_GET['identity']) {
+	if (!empty($_GET['identity'])) {
 		$_POST['identity'] = $_GET['identity'];
 		manage_post($a);
 		return;
diff --git a/mod/viewcontacts.php b/mod/viewcontacts.php
index f0a5f0cd85..3b3579ce76 100644
--- a/mod/viewcontacts.php
+++ b/mod/viewcontacts.php
@@ -11,36 +11,39 @@ use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Profile;
 use Friendica\Util\Proxy as ProxyUtils;
+use Friendica\Core\System;
 
 function viewcontacts_init(App $a)
 {
-	if ((Config::get('system', 'block_public')) && (! local_user()) && (! remote_user())) {
+	if (Config::get('system', 'block_public') && !local_user() && !remote_user()) {
 		return;
 	}
 
+	if ($a->argc < 2) {
+		System::httpExit(403, ["title" => L10n::t('Access denied.')]);
+	}
+
 	Nav::setSelected('home');
 
-	if ($a->argc > 1) {
-		$nick = $a->argv[1];
-		$r = q("SELECT * FROM `user` WHERE `nickname` = '%s' AND `blocked` = 0 LIMIT 1",
-			DBA::escape($nick)
-		);
+	$nick = $a->argv[1];
+	$r = q("SELECT * FROM `user` WHERE `nickname` = '%s' AND `blocked` = 0 LIMIT 1",
+		DBA::escape($nick)
+	);
 
-		if (! DBA::isResult($r)) {
-			return;
-		}
-
-		$a->data['user'] = $r[0];
-		$a->profile_uid = $r[0]['uid'];
-		$is_owner = (local_user() && (local_user() == $a->profile_uid));
-
-		Profile::load($a, $a->argv[1]);
+	if (!DBA::isResult($r)) {
+		return;
 	}
+
+	$a->data['user'] = $r[0];
+	$a->profile_uid = $r[0]['uid'];
+	$is_owner = (local_user() && (local_user() == $a->profile_uid));
+
+	Profile::load($a, $a->argv[1]);
 }
 
 function viewcontacts_content(App $a)
 {
-	if ((Config::get('system', 'block_public')) && (! local_user()) && (! remote_user())) {
+	if (Config::get('system', 'block_public') && !local_user() && !remote_user()) {
 		notice(L10n::t('Public access denied.') . EOL);
 		return;
 	}
@@ -52,7 +55,7 @@ function viewcontacts_content(App $a)
 	// tabs
 	$o .= Profile::getTabs($a, $is_owner, $a->data['user']['nickname']);
 
-	if (((! count($a->profile)) || ($a->profile['hide-friends']))) {
+	if (!count($a->profile) || $a->profile['hide-friends']) {
 		notice(L10n::t('Permission denied.') . EOL);
 		return $o;
 	}
@@ -123,6 +126,5 @@ function viewcontacts_content(App $a)
 		'$paginate' => paginate($a),
 	]);
 
-
 	return $o;
 }
diff --git a/src/Model/Contact.php b/src/Model/Contact.php
index d93e0cb57e..52eaa437f1 100644
--- a/src/Model/Contact.php
+++ b/src/Model/Contact.php
@@ -339,6 +339,11 @@ class Contact extends BaseObject
 			$item = [];
 			$item['verb'] = NAMESPACE_OSTATUS . "/unfollow";
 			$item['follow'] = $contact["url"];
+			$item['body'] = '';
+			$item['title'] = '';
+			$item['guid'] = '';
+			$item['tag'] = '';
+			$item['attach'] = '';
 			$slap = OStatus::salmon($item, $user);
 
 			if (!empty($contact['notify'])) {
@@ -1505,6 +1510,11 @@ class Contact extends BaseObject
 				$item = [];
 				$item['verb'] = ACTIVITY_FOLLOW;
 				$item['follow'] = $contact["url"];
+				$item['body'] = '';
+				$item['title'] = '';
+				$item['guid'] = '';
+				$item['tag'] = '';
+				$item['attach'] = '';
 				$slap = OStatus::salmon($item, $r[0]);
 				if (!empty($contact['notify'])) {
 					Salmon::slapper($r[0], $contact['notify'], $slap);
diff --git a/src/Model/Profile.php b/src/Model/Profile.php
index 9d1b002a79..3ac147396d 100644
--- a/src/Model/Profile.php
+++ b/src/Model/Profile.php
@@ -199,7 +199,7 @@ class Profile
 	 */
 	public static function getByNickname($nickname, $uid = 0, $profile_id = 0)
 	{
-		if (remote_user() && count($_SESSION['remote'])) {
+		if (remote_user() && !empty($_SESSION['remote'])) {
 			foreach ($_SESSION['remote'] as $visitor) {
 				if ($visitor['uid'] == $uid) {
 					$contact = DBA::selectFirst('contact', ['profile-id'], ['id' => $visitor['cid']]);
@@ -293,7 +293,7 @@ class Profile
 		$connect = $profile['uid'] != local_user() ? L10n::t('Connect') : false;
 
 		// don't show connect link to authenticated visitors either
-		if (remote_user() && count($_SESSION['remote'])) {
+		if (remote_user() && !empty($_SESSION['remote'])) {
 			foreach ($_SESSION['remote'] as $visitor) {
 				if ($visitor['uid'] == $profile['uid']) {
 					$connect = false;
diff --git a/src/Protocol/Diaspora.php b/src/Protocol/Diaspora.php
index 82255eac9f..e463857857 100644
--- a/src/Protocol/Diaspora.php
+++ b/src/Protocol/Diaspora.php
@@ -4089,7 +4089,7 @@ class Diaspora
 				$arr = explode(' ', $profile['pub_keywords']);
 				if (count($arr)) {
 					for ($x = 0; $x < 5; $x ++) {
-						if (trim($arr[$x])) {
+						if (!empty($arr[$x])) {
 							$tags .= '#'. trim($arr[$x]) .' ';
 						}
 					}