diff --git a/bridges/FilterBridge.php b/bridges/FilterBridge.php
index 1add47f4..3448a8c7 100644
--- a/bridges/FilterBridge.php
+++ b/bridges/FilterBridge.php
@@ -77,7 +77,7 @@ class FilterBridge extends FeedExpander
     {
         $url = $this->getInput('url');
         if (!Url::validate($url)) {
-            returnClientError('The url parameter must either refer to http or https protocol.');
+            throw new \Exception('The url parameter must either refer to http or https protocol.');
         }
         $this->collectExpandableDatas($this->getURI());
     }
diff --git a/bridges/TrelloBridge.php b/bridges/TrelloBridge.php
index cab2bde2..42651fd1 100644
--- a/bridges/TrelloBridge.php
+++ b/bridges/TrelloBridge.php
@@ -553,10 +553,8 @@ class TrelloBridge extends BridgeAbstract
 
     private function queryAPI($path, $params = [])
     {
-        $data = json_decode(getContents('https://trello.com/1/'
-            . $path
-            . '?'
-            . http_build_query($params)));
+        $url = 'https://trello.com/1/' . $path . '?' . http_build_query($params);
+        $data = json_decode(getContents($url));
         return $data;
     }
 
@@ -576,33 +574,21 @@ class TrelloBridge extends BridgeAbstract
                 && !$textOnly
                 && isset($entity->originalUrl)
             ) {
-                $string = '<p><a href="'
-                    . $entity->originalUrl
-                    . '"><img src="'
-                    . $entity->previewUrl
-                    . '"></a></p>';
+                $string = sprintf(
+                    '<p><a href="%s"><img src="%s"></a></p>',
+                    $entity->originalUrl,
+                    $entity->previewUrl ?? ''
+                );
             } elseif ($type === 'card' && !$textOnly) {
-                $string = '<a href="https://trello.com/c/'
-                    . $entity->shortLink
-                    . '">'
-                    . $entity->text
-                    . '</a>';
+                $string = sprintf('<a href="https://trello.com/c/%s">%s</a>', $entity->shortLink, $entity->text);
             } elseif ($type === 'member' && !$textOnly) {
-                $string = '<a href="https://trello.com/'
-                    . $entity->username
-                    . '">'
-                    . $entity->text
-                    . '</a>';
+                $string = sprintf('<a href="https://trello.com/%s">%s</a>', $entity->username, $entity->text);
             } elseif ($type === 'date') {
                 $string = gmdate('M j, Y \a\t g:i A T', strtotime($entity->date));
             } elseif ($type === 'translatable') {
                 $string = self::ACTION_TEXTS[$entity->translationKey];
             } else {
-                if (isset($entity->text)) {
-                    $string = $entity->text;
-                } else {
-                    $string = '';
-                }
+                $string = $entity->text ?? '';
             }
             $strings['{' . $entity_name . '}'] = $string;
         }
diff --git a/bridges/TwitchBridge.php b/bridges/TwitchBridge.php
index 9e70944e..424cd6e3 100644
--- a/bridges/TwitchBridge.php
+++ b/bridges/TwitchBridge.php
@@ -99,7 +99,7 @@ EOD;
         $user = $data->user;
         if ($user->videos === null) {
             // twitch regularly does this for unknown reasons
-            $this->logger->info('Twitch returned empty set of videos', ['data' => $data]);
+            //$this->logger->info('Twitch returned empty set of videos', ['data' => $data]);
             return;
         }
 
diff --git a/formats/HtmlFormat.php b/formats/HtmlFormat.php
index 1e2f60e6..37ef3a93 100644
--- a/formats/HtmlFormat.php
+++ b/formats/HtmlFormat.php
@@ -6,7 +6,7 @@ class HtmlFormat extends FormatAbstract
 
     public function stringify()
     {
-        // This query string comes in already url decoded
+        // This query string is url encoded
         $queryString = $_SERVER['QUERY_STRING'];
 
         $feedArray = $this->getFeed();
diff --git a/lib/BridgeAbstract.php b/lib/BridgeAbstract.php
index 1456e1c3..2467dec6 100644
--- a/lib/BridgeAbstract.php
+++ b/lib/BridgeAbstract.php
@@ -6,8 +6,17 @@ abstract class BridgeAbstract
     const URI = '';
     const DONATION_URI = '';
     const DESCRIPTION = 'No description provided';
+
+    /**
+     * Preferably a github username
+     */
     const MAINTAINER = 'No maintainer';
+
+    /**
+     * Cache TTL in seconds
+     */
     const CACHE_TIMEOUT = 3600;
+
     const CONFIGURATION = [];
     const PARAMETERS = [];
     const TEST_DETECT_PARAMETERS = [];
diff --git a/lib/contents.php b/lib/contents.php
index 43db8c03..ba6dd531 100644
--- a/lib/contents.php
+++ b/lib/contents.php
@@ -17,6 +17,8 @@ function getContents(
     $httpClient = RssBridge::getHttpClient();
     $cache = RssBridge::getCache();
 
+    // TODO: consider url validation at this point
+
     $httpHeadersNormalized = [];
     foreach ($httpHeaders as $httpHeader) {
         $parts = explode(':', $httpHeader);