diff --git a/src/Content/Conversation.php b/src/Content/Conversation.php
index 1088497983..5bb47b23b1 100644
--- a/src/Content/Conversation.php
+++ b/src/Content/Conversation.php
@@ -582,7 +582,7 @@ class Conversation
 
 					$uriids[] = $item['uri-id'];
 
-					if (!$this->item->visibleActivity($item)) {
+					if (!$this->item->isVisibleActivity($item)) {
 						continue;
 					}
 
@@ -745,7 +745,7 @@ class Conversation
 						continue;
 					}
 
-					if (!$this->item->visibleActivity($item)) {
+					if (!$this->item->isVisibleActivity($item)) {
 						continue;
 					}
 
diff --git a/src/Content/Item.php b/src/Content/Item.php
index 66dcde0ff3..ccd3396c22 100644
--- a/src/Content/Item.php
+++ b/src/Content/Item.php
@@ -85,7 +85,7 @@ class Item
 	 *       ]
 	 *  ]
 	 */
-	public function determineCategoriesTerms(array $item, int $uid = 0)
+	public function determineCategoriesTerms(array $item, int $uid = 0): array
 	{
 		$categories = [];
 		$folders = [];
@@ -141,16 +141,16 @@ class Item
 	 * This function removes the tag $tag from the text $body and replaces it with
 	 * the appropriate link.
 	 *
-	 * @param string  $body        the text to replace the tag in
-	 * @param integer $profile_uid the user id to replace the tag for (0 = anyone)
-	 * @param string  $tag         the tag to replace
-	 * @param string  $network     The network of the post
+	 * @param string $body        the text to replace the tag in
+	 * @param int    $profile_uid the user id to replace the tag for (0 = anyone)
+	 * @param string $tag         the tag to replace
+	 * @param string $network     The network of the post
 	 *
-	 * @return array|bool ['replaced' => $replaced, 'contact' => $contact];
+	 * @return array|bool ['replaced' => $replaced, 'contact' => $contact] or "false" on if already replaced
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 * @throws \ImagickException
 	 */
-	public static function replaceTag(&$body, $profile_uid, $tag, $network = '')
+	public static function replaceTag(string &$body, int $profile_uid, string $tag, string $network = '')
 	{
 		$replaced = false;
 
@@ -244,16 +244,17 @@ class Item
 	/**
 	 * Render actions localized
 	 *
-	 * @param $item
+	 * @param array $item
+	 * @return void
 	 * @throws ImagickException
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public function localize(&$item)
+	public function localize(array &$item)
 	{
 		$this->profiler->startRecording('rendering');
 		/// @todo The following functionality needs to be cleaned up.
 		if (!empty($item['verb'])) {
-			$xmlhead = "<" . "?xml version='1.0' encoding='UTF-8' ?" . ">";
+			$xmlhead = '<?xml version="1.0" encoding="UTF-8" ?>';
 
 			if (stristr($item['verb'], Activity::POKE)) {
 				$verb = urldecode(substr($item['verb'], strpos($item['verb'],'#') + 1));
@@ -261,7 +262,7 @@ class Item
 					$this->profiler->stopRecording();
 					return;
 				}
-				if ($item['object-type'] == "" || $item['object-type'] !== Activity\ObjectType::PERSON) {
+				if ($item['object-type'] == '' || $item['object-type'] !== Activity\ObjectType::PERSON) {
 					$this->profiler->stopRecording();
 					return;
 				}
@@ -270,18 +271,22 @@ class Item
 
 				$Bname = $obj->title;
 				$Blink = $obj->id;
-				$Bphoto = "";
+				$Bphoto = '';
 
 				foreach ($obj->link as $l) {
 					$atts = $l->attributes();
 					switch ($atts['rel']) {
-						case "alternate": $Blink = $atts['href'];
-						case "photo": $Bphoto = $atts['href'];
+						case 'alternate': $Blink = $atts['href'];
+						case 'photo': $Bphoto = $atts['href'];
 					}
 				}
 
-				$author = ['uid' => 0, 'id' => $item['author-id'],
-					'network' => $item['author-network'], 'url' => $item['author-link']];
+				$author = [
+					'uid' => 0,
+					'id' => $item['author-id'],
+					'network' => $item['author-network'],
+					'url' => $item['author-link'],
+				];
 				$A = '[url=' . Contact::magicLinkByContact($author) . ']' . $item['author-name'] . '[/url]';
 
 				if (!empty($Blink)) {
@@ -290,7 +295,7 @@ class Item
 					$B = '';
 				}
 
-				if ($Bphoto != "" && !empty($Blink)) {
+				if ($Bphoto != '' && !empty($Blink)) {
 					$Bphoto = '[url=' . Contact::magicLink($Blink) . '][img=80x80]' . $Bphoto . '[/img][/url]';
 				}
 
@@ -305,9 +310,7 @@ class Item
 				$txt = str_replace($poked_t, $this->l10n->t($verb), $txt);
 
 				// then do the sprintf on the translation string
-
 				$item['body'] = sprintf($txt, $A, $B) . "\n\n\n" . $Bphoto;
-
 			}
 
 			if ($this->activity->match($item['verb'], Activity::TAG)) {
@@ -319,12 +322,20 @@ class Item
 					return;
 				}
 
-				$author_arr = ['uid' => 0, 'id' => $item['author-id'],
-					'network' => $item['author-network'], 'url' => $item['author-link']];
+				$author_arr = [
+					'uid' => 0,
+					'id' => $item['author-id'],
+					'network' => $item['author-network'],
+					'url' => $item['author-link'],
+				];
 				$author  = '[url=' . Contact::magicLinkByContact($author_arr) . ']' . $item['author-name'] . '[/url]';
 
-				$author_arr = ['uid' => 0, 'id' => $obj['author-id'],
-					'network' => $obj['author-network'], 'url' => $obj['author-link']];
+				$author_arr = [
+					'uid' => 0,
+					'id' => $obj['author-id'],
+					'network' => $obj['author-network'],
+					'url' => $obj['author-link'],
+				];
 				$objauthor  = '[url=' . Contact::magicLinkByContact($author_arr) . ']' . $obj['author-name'] . '[/url]';
 
 				switch ($obj['verb']) {
@@ -337,6 +348,7 @@ class Item
 								$post_type = $this->l10n->t('status');
 						}
 						break;
+
 					default:
 						if ($obj['resource-id']) {
 							$post_type = $this->l10n->t('photo');
@@ -360,25 +372,29 @@ class Item
 		$this->profiler->stopRecording();
 	}
 
-	public function photoMenu($item, string $formSecurityToken)
+	/**
+	 * Renders photo menu based on item
+	 *
+	 * @param array $item
+	 * @param string $formSecurityToken
+	 * @return string
+	 */
+	public function photoMenu(array $item, string $formSecurityToken): string
 	{
 		$this->profiler->startRecording('rendering');
-		$sub_link = '';
-		$poke_link = '';
-		$contact_url = '';
-		$pm_url = '';
-		$status_link = '';
-		$photos_link = '';
-		$posts_link = '';
-		$block_link = '';
-		$ignore_link = '';
+		$sub_link = $poke_link = $contact_url = $pm_url = $status_link = '';
+		$photos_link = $posts_link = $block_link = $ignore_link = '';
 
 		if (local_user() && local_user() == $item['uid'] && $item['gravity'] == GRAVITY_PARENT && !$item['self'] && !$item['mention']) {
 			$sub_link = 'javascript:doFollowThread(' . $item['id'] . '); return false;';
 		}
 
-		$author = ['uid' => 0, 'id' => $item['author-id'],
-			'network' => $item['author-network'], 'url' => $item['author-link']];
+		$author = [
+			'uid' => 0,
+			'id' => $item['author-id'],
+			'network' => $item['author-network'],
+			'url' => $item['author-link'],
+		];
 		$profile_link = Contact::magicLinkByContact($author, $item['author-link']);
 		$sparkle = (strpos($profile_link, 'redir/') === 0);
 
@@ -435,7 +451,7 @@ class Item
 			}
 
 			if ($network == Protocol::DFRN) {
-				$menu[$this->l10n->t("Poke")] = $poke_link;
+				$menu[$this->l10n->t('Poke')] = $poke_link;
 			}
 
 			if ((($cid == 0) || ($rel == Contact::FOLLOWER)) &&
@@ -465,24 +481,28 @@ class Item
 		return $o;
 	}
 
-	public function visibleActivity($item) {
-
+	/**
+	 * Checks if the activity is visible to current user
+	 *
+	 * @param array $item Activity item
+	 * @return bool Whether the item is visible to the user
+	 */
+	public function isVisibleActivity(array $item): bool
+	{
+		// Empty verb or hidden?
 		if (empty($item['verb']) || $this->activity->isHidden($item['verb'])) {
 			return false;
 		}
 
-		// @TODO below if() block can be rewritten to a single line: $isVisible = allConditionsHere;
-		if ($this->activity->match($item['verb'], Activity::FOLLOW) &&
+		// Check conditions
+		return (!($this->activity->match($item['verb'], Activity::FOLLOW) &&
 			$item['object-type'] === Activity\ObjectType::NOTE &&
 			empty($item['self']) &&
-			$item['uid'] == local_user()) {
-			return false;
-		}
-
-		return true;
+			$item['uid'] == local_user())
+		);
 	}
 
-	public function expandTags(array $item, bool $setPermissions = false)
+	public function expandTags(array $item, bool $setPermissions = false): array
 	{
 		// Look for any tags and linkify them
 		$item['inform'] = '';
diff --git a/src/Content/Nav.php b/src/Content/Nav.php
index c30a157067..77f068863a 100644
--- a/src/Content/Nav.php
+++ b/src/Content/Nav.php
@@ -62,7 +62,7 @@ class Nav
 	 *
 	 * @param string $item
 	 */
-	public static function setSelected($item)
+	public static function setSelected(string $item)
 	{
 		self::$selected[$item] = 'selected';
 	}
@@ -74,7 +74,7 @@ class Nav
 	 * @return string
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function build(App $a)
+	public static function build(App $a): string
 	{
 		// Placeholder div for popup panel
 		$nav = '<div id="panel" style="display: none;"></div>';
@@ -106,7 +106,7 @@ class Nav
 	 *
 	 * @return array
 	 */
-	public static function getAppMenu()
+	public static function getAppMenu(): array
 	{
 		if (is_null(self::$app_menu)) {
 			self::populateAppMenu();
@@ -117,6 +117,8 @@ class Nav
 
 	/**
 	 * Fills the apps static variable with apps that require a menu
+	 *
+	 * @return void
 	 */
 	private static function populateAppMenu()
 	{
diff --git a/src/Content/OEmbed.php b/src/Content/OEmbed.php
index dbba99fcff..498a65e33b 100644
--- a/src/Content/OEmbed.php
+++ b/src/Content/OEmbed.php
@@ -49,7 +49,13 @@ use Friendica\Util\Strings;
  */
 class OEmbed
 {
-	public static function replaceCallback($matches)
+	/**
+	 * Callback for fetching URL, checking allowance and returning formatted HTML
+	 *
+	 * @param array $matches
+	 * @return string Formatted HTML
+	 */
+	public static function replaceCallback(array $matches): string
 	{
 		$embedurl = $matches[1];
 		$j = self::fetchURL($embedurl, !self::isAllowedURL($embedurl));
@@ -68,7 +74,7 @@ class OEmbed
 	 * @return \Friendica\Object\OEmbed
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function fetchURL($embedurl, bool $no_rich_type = false, bool $use_parseurl = true)
+	public static function fetchURL(string $embedurl, bool $no_rich_type = false, bool $use_parseurl = true): \Friendica\Object\OEmbed
 	{
 		$embedurl = trim($embedurl, '\'"');
 
@@ -209,12 +215,18 @@ class OEmbed
 		return $oembed;
 	}
 
-	private static function formatObject(\Friendica\Object\OEmbed $oembed)
+	/**
+	 * Returns a formatted string from OEmbed object
+	 *
+	 * @param \Friendica\Object\OEmbed $oembed
+	 * @return string
+	 */
+	private static function formatObject(\Friendica\Object\OEmbed $oembed): string
 	{
 		$ret = '<div class="oembed ' . $oembed->type . '">';
 
 		switch ($oembed->type) {
-			case "video":
+			case 'video':
 				if ($oembed->thumbnail_url) {
 					$tw = (isset($oembed->thumbnail_width) && intval($oembed->thumbnail_width)) ? $oembed->thumbnail_width : 200;
 					$th = (isset($oembed->thumbnail_height) && intval($oembed->thumbnail_height)) ? $oembed->thumbnail_height : 180;
@@ -236,14 +248,14 @@ class OEmbed
 				}
 				break;
 
-			case "photo":
+			case 'photo':
 				$ret .= '<img width="' . $oembed->width . '" src="' . Proxy::proxifyUrl($oembed->url) . '">';
 				break;
 
-			case "link":
+			case 'link':
 				break;
 
-			case "rich":
+			case 'rich':
 				$ret .= Proxy::proxifyHtml($oembed->html);
 				break;
 		}
@@ -292,9 +304,15 @@ class OEmbed
 		return str_replace("\n", "", $ret);
 	}
 
-	public static function BBCode2HTML($text)
+	/**
+	 * Converts BBCode to HTML code
+	 *
+	 * @param string $text
+	 * @return string
+	 */
+	public static function BBCode2HTML(string $text): string
 	{
-		$stopoembed = DI::config()->get("system", "no_oembed");
+		$stopoembed = DI::config()->get('system', 'no_oembed');
 		if ($stopoembed == true) {
 			return preg_replace("/\[embed\](.+?)\[\/embed\]/is", "<!-- oembed $1 --><i>" . DI::l10n()->t('Embedding disabled') . " : $1</i><!-- /oembed $1 -->", $text);
 		}
@@ -305,14 +323,13 @@ class OEmbed
 	 * Find <span class='oembed'>..<a href='url' rel='oembed'>..</a></span>
 	 * and replace it with [embed]url[/embed]
 	 *
-	 * @param $text
+	 * @param string $text
 	 * @return string
 	 */
-	public static function HTML2BBCode($text)
+	public static function HTML2BBCode(string $text): string
 	{
 		// start parser only if 'oembed' is in text
-		if (strpos($text, "oembed")) {
-
+		if (strpos($text, 'oembed')) {
 			// convert non ascii chars to html entities
 			$html_text = mb_convert_encoding($text, 'HTML-ENTITIES', mb_detect_encoding($text));
 
@@ -323,17 +340,17 @@ class OEmbed
 			}
 			$xpath = new DOMXPath($dom);
 
-			$xattr = self::buildXPath("class", "oembed");
+			$xattr = self::buildXPath('class', 'oembed');
 			$entries = $xpath->query("//div[$xattr]");
 
 			$xattr = "@rel='oembed'"; //oe_build_xpath("rel","oembed");
 			foreach ($entries as $e) {
 				$href = $xpath->evaluate("a[$xattr]/@href", $e)->item(0)->nodeValue;
 				if (!is_null($href)) {
-					$e->parentNode->replaceChild(new DOMText("[embed]" . $href . "[/embed]"), $e);
+					$e->parentNode->replaceChild(new DOMText('[embed]' . $href . '[/embed]'), $e);
 				}
 			}
-			return self::getInnerHTML($dom->getElementsByTagName("body")->item(0));
+			return self::getInnerHTML($dom->getElementsByTagName('body')->item(0));
 		} else {
 			return $text;
 		}
@@ -346,7 +363,7 @@ class OEmbed
 	 * @return boolean
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function isAllowedURL($url)
+	public static function isAllowedURL(string $url): bool
 	{
 		if (!DI::config()->get('system', 'no_oembed_rich_content')) {
 			return true;
@@ -367,7 +384,14 @@ class OEmbed
 		return Network::isDomainAllowed($domain, $allowed);
 	}
 
-	public static function getHTML($url, $title = null)
+	/**
+	 * Returns a formmated HTML code from given URL and sets optional title
+	 *
+	 * @param string $url URL to fetch
+	 * @param string $title Optional title (default: what comes from OEmbed object)
+	 * @return string Formatted HTML
+	 */
+	public static function getHTML(string $url, string $title = '')
 	{
 		$o = self::fetchURL($url, !self::isAllowedURL($url));
 
@@ -401,12 +425,12 @@ class OEmbed
 	 * @param string $src Original remote URL to embed
 	 * @param string $width
 	 * @param string $height
-	 * @return string formatted HTML
+	 * @return string Formatted HTML
 	 *
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 * @see   oembed_format_object()
 	 */
-	private static function iframe($src, $width, $height)
+	private static function iframe(string $src, string $width, string $height): string
 	{
 		if (!$height || strstr($height, '%')) {
 			$height = '200';
@@ -427,7 +451,7 @@ class OEmbed
 	 * @param string $value Value to search in a space-separated list
 	 * @return string
 	 */
-	private static function buildXPath($attr, $value)
+	private static function buildXPath(string $attr, $value): string
 	{
 		// https://www.westhoffswelt.de/blog/2009/6/9/select-html-elements-with-more-than-one-css-class-using-xpath
 		return "contains(normalize-space(@$attr), ' $value ') or substring(normalize-space(@$attr), 1, string-length('$value') + 1) = '$value ' or substring(normalize-space(@$attr), string-length(@$attr) - string-length('$value')) = ' $value' or @$attr = '$value'";
@@ -439,7 +463,7 @@ class OEmbed
 	 * @param DOMNode $node
 	 * @return string
 	 */
-	private static function getInnerHTML(DOMNode $node)
+	private static function getInnerHTML(DOMNode $node): string
 	{
 		$innerHTML = '';
 		$children = $node->childNodes;
diff --git a/src/Content/PageInfo.php b/src/Content/PageInfo.php
index 41ecb3d7fa..71ffebc444 100644
--- a/src/Content/PageInfo.php
+++ b/src/Content/PageInfo.php
@@ -64,7 +64,7 @@ class PageInfo
 	 * @return string
 	 * @throws HTTPException\InternalServerErrorException
 	 */
-	public static function appendDataToBody(string $body, array $data, bool $no_photos = false)
+	public static function appendDataToBody(string $body, array $data, bool $no_photos = false): string
 	{
 		// Only one [attachment] tag per body is allowed
 		$existingAttachmentPos = strpos($body, '[attachment');
@@ -90,7 +90,7 @@ class PageInfo
 	 * @return string
 	 * @throws HTTPException\InternalServerErrorException
 	 */
-	public static function getFooterFromUrl(string $url, bool $no_photos = false, string $photo = '', bool $keywords = false, string $keyword_denylist = '')
+	public static function getFooterFromUrl(string $url, bool $no_photos = false, string $photo = '', bool $keywords = false, string $keyword_denylist = ''): string
 	{
 		$data = self::queryUrl($url, $photo, $keywords, $keyword_denylist);
 
@@ -103,7 +103,7 @@ class PageInfo
 	 * @return string
 	 * @throws HTTPException\InternalServerErrorException
 	 */
-	public static function getFooterFromData(array $data, bool $no_photos = false)
+	public static function getFooterFromData(array $data, bool $no_photos = false): string
 	{
 		Hook::callAll('page_info_data', $data);
 
@@ -220,7 +220,7 @@ class PageInfo
 	 * @return array
 	 * @throws HTTPException\InternalServerErrorException
 	 */
-	public static function getTagsFromUrl(string $url, string $photo = '', string $keyword_denylist = '')
+	public static function getTagsFromUrl(string $url, string $photo = '', string $keyword_denylist = ''): array
 	{
 		$data = self::queryUrl($url, $photo, true, $keyword_denylist);
 
@@ -282,7 +282,7 @@ class PageInfo
 	 * @param string $url
 	 * @return string
 	 */
-	protected static function stripTrailingUrlFromBody(string $body, string $url)
+	protected static function stripTrailingUrlFromBody(string $body, string $url): string
 	{
 		$quotedUrl = preg_quote($url, '#');
 		$body = preg_replace_callback("#(?:
diff --git a/src/Content/Pager.php b/src/Content/Pager.php
index 5109fd1de3..98b885d425 100644
--- a/src/Content/Pager.php
+++ b/src/Content/Pager.php
@@ -48,11 +48,11 @@ class Pager
 	 *
 	 * Guesses the page number from the GET parameter 'page'.
 	 *
-	 * @param L10n    $l10n
-	 * @param string  $queryString  The query string of the current page
-	 * @param integer $itemsPerPage An optional number of items per page to override the default value
+	 * @param L10n   $l10n
+	 * @param string $queryString  The query string of the current page
+	 * @param int    $itemsPerPage An optional number of items per page to override the default value
 	 */
-	public function __construct(L10n $l10n, $queryString, $itemsPerPage = 50)
+	public function __construct(L10n $l10n, string $queryString, int $itemsPerPage = 50)
 	{
 		$this->l10n = $l10n;
 
@@ -64,9 +64,9 @@ class Pager
 	/**
 	 * Returns the start offset for a LIMIT clause. Starts at 0.
 	 *
-	 * @return integer
+	 * @return int
 	 */
-	public function getStart()
+	public function getStart(): int
 	{
 		return max(0, ($this->page * $this->itemsPerPage) - $this->itemsPerPage);
 	}
@@ -74,9 +74,9 @@ class Pager
 	/**
 	 * Returns the number of items per page
 	 *
-	 * @return integer
+	 * @return int
 	 */
-	public function getItemsPerPage()
+	public function getItemsPerPage(): int
 	{
 		return $this->itemsPerPage;
 	}
@@ -86,7 +86,7 @@ class Pager
 	 *
 	 * @return int
 	 */
-	public function getPage()
+	public function getPage(): int
 	{
 		return $this->page;
 	}
@@ -108,9 +108,9 @@ class Pager
 	/**
 	 * Sets the number of items per page, 1 minimum.
 	 *
-	 * @param integer $itemsPerPage
+	 * @param int $itemsPerPage
 	 */
-	public function setItemsPerPage($itemsPerPage)
+	public function setItemsPerPage(int $itemsPerPage)
 	{
 		$this->itemsPerPage = max(1, intval($itemsPerPage));
 	}
@@ -118,11 +118,11 @@ class Pager
 	/**
 	 * Sets the current page number. Starts at 1.
 	 *
-	 * @param integer $page
+	 * @param int $page
 	 */
-	public function setPage($page)
+	public function setPage(int $page)
 	{
-		$this->page = max(1, intval($page));
+		$this->page = max(1, $page);
 	}
 
 	/**
@@ -132,7 +132,7 @@ class Pager
 	 *
 	 * @param string $queryString
 	 */
-	public function setQueryString($queryString)
+	public function setQueryString(string $queryString)
 	{
 		$stripped = preg_replace('/([&?]page=[0-9]*)/', '', $queryString);
 
diff --git a/src/Content/Smilies.php b/src/Content/Smilies.php
index 411f03b463..4a36e0911e 100644
--- a/src/Content/Smilies.php
+++ b/src/Content/Smilies.php
@@ -39,10 +39,9 @@ class Smilies
 	 * @param array  $b              Array of emoticons
 	 * @param string $smiley         The text smilie
 	 * @param string $representation The replacement
-	 *
 	 * @return void
 	 */
-	public static function add(&$b, $smiley, $representation)
+	public static function add(array &$b, string $smiley, string $representation)
 	{
 		$found = array_search($smiley, $b['texts']);
 
@@ -66,7 +65,7 @@ class Smilies
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 * @hook  smilie ('texts' => smilies texts array, 'icons' => smilies html array)
 	 */
-	public static function getList()
+	public static function getList(): array
 	{
 		$texts =  [
 			'&lt;3',
@@ -169,7 +168,7 @@ class Smilies
 	 *
 	 * @return string $subject with all substrings in the $search array replaced by the values in the $replace array
 	 */
-	private static function strOrigReplace($search, $replace, $subject)
+	private static function strOrigReplace(array $search, array $replace, string $subject): string
 	{
 		return strtr($subject, array_combine($search, $replace));
 	}
@@ -191,7 +190,7 @@ class Smilies
 	 * @return string HTML Output of the Smilie
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function replace($s, $no_images = false)
+	public static function replace(string $s, bool $no_images = false): string
 	{
 		$smilies = self::getList();
 
@@ -211,7 +210,7 @@ class Smilies
 	 * @return string
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function replaceFromArray($text, array $smilies, $no_images = false)
+	public static function replaceFromArray(string $text, array $smilies, bool $no_images = false): string
 	{
 		if (intval(DI::config()->get('system', 'no_smilies'))
 			|| (local_user() && intval(DI::pConfig()->get(local_user(), 'system', 'no_smilies')))
@@ -248,7 +247,7 @@ class Smilies
 	 *
 	 * @return string base64 encoded string
 	 */
-	private static function encode($m)
+	private static function encode(string $m): string
 	{
 		return '<' . $m[1] . '>' . Strings::base64UrlEncode($m[2]) . '</' . $m[1] . '>';
 	}
@@ -259,7 +258,7 @@ class Smilies
 	 * @return string base64 decoded string
 	 * @throws \Exception
 	 */
-	private static function decode($m)
+	private static function decode(string $m): string
 	{
 		return '<' . $m[1] . '>' . Strings::base64UrlDecode($m[2]) . '</' . $m[1] . '>';
 	}
@@ -274,7 +273,7 @@ class Smilies
 	 *
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	private static function pregHeart($x)
+	private static function pregHeart(string $x): string
 	{
 		if (strlen($x[1]) == 1) {
 			return $x[0];
diff --git a/src/Content/Widget.php b/src/Content/Widget.php
index a2a3b3257b..9295818113 100644
--- a/src/Content/Widget.php
+++ b/src/Content/Widget.php
@@ -225,7 +225,7 @@ class Widget
 	 * @return string
 	 * @throws \Exception
 	 */
-	public static function contactRels($baseurl, $selected = '')
+	public static function contactRels(string $baseurl, string $selected = ''): string
 	{
 		if (!local_user()) {
 			return '';
@@ -256,7 +256,7 @@ class Widget
 	 * @return string
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function networks($baseurl, $selected = '')
+	public static function networks(string $baseurl, string $selected = ''): string
 	{
 		if (!local_user()) {
 			return '';
@@ -294,10 +294,10 @@ class Widget
 	 *
 	 * @param string $baseurl  baseurl
 	 * @param string $selected optional, default empty
-	 * @return string|void
+	 * @return string
 	 * @throws \Exception
 	 */
-	public static function fileAs($baseurl, $selected = '')
+	public static function fileAs(string $baseurl, string $selected = ''): string
 	{
 		if (!local_user()) {
 			return '';
@@ -325,10 +325,10 @@ class Widget
 	 * @param int    $uid      Id of the user owning the categories
 	 * @param string $baseurl  Base page URL
 	 * @param string $selected Selected category
-	 * @return string|void
+	 * @return string
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function categories(int $uid, string $baseurl, string $selected = '')
+	public static function categories(int $uid, string $baseurl, string $selected = ''): string
 	{
 		if (!Feature::isEnabled($uid, 'categories')) {
 			return '';
@@ -355,11 +355,11 @@ class Widget
 	 *
 	 * @param int    $uid      Viewed profile user ID
 	 * @param string $nickname Viewed profile user nickname
-	 * @return string|void
+	 * @return string
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 * @throws \ImagickException
 	 */
-	public static function commonFriendsVisitor(int $uid, string $nickname)
+	public static function commonFriendsVisitor(int $uid, string $nickname): string
 	{
 		if (local_user() == $uid) {
 			return '';
@@ -416,7 +416,7 @@ class Widget
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 * @throws \ImagickException
 	 */
-	public static function tagCloud(int $uid, int $limit = 50)
+	public static function tagCloud(int $uid, int $limit = 50): string
 	{
 		if (empty($uid)) {
 			return '';
@@ -441,7 +441,7 @@ class Widget
 	 * @return string
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function postedByYear(string $url, int $uid, bool $wall)
+	public static function postedByYear(string $url, int $uid, bool $wall): string
 	{
 		$o = '';
 
@@ -515,7 +515,7 @@ class Widget
 	 * @param int    $accounttype Acount type
 	 * @return string
 	 */
-	public static function accounttypes(string $base, $accounttype)
+	public static function accounttypes(string $base, int $accounttype): string
 	{
 		$accounts = [
 			['ref' => 'person', 'name' => DI::l10n()->t('Persons')],
diff --git a/src/Object/Post.php b/src/Object/Post.php
index f15f96019d..fe271b5a87 100644
--- a/src/Object/Post.php
+++ b/src/Object/Post.php
@@ -106,7 +106,7 @@ class Post
 				// Only add will be displayed
 				if ($item['network'] === Protocol::MAIL && local_user() != $item['uid']) {
 					continue;
-				} elseif (!DI::contentItem()->visibleActivity($item)) {
+				} elseif (!DI::contentItem()->isVisibleActivity($item)) {
 					continue;
 				}