A lot of code cleanup and code sanitation done.

pub/api/classes/imageProcessor.php

@@ -115,7 +115,7 @@ class imageProcessor
         return in_array($mime, ['image/png', 'image/webp']);
     }
 
-    private function setTransparentCanvas($image, $width, $height)
+    private function setTransparentCanvas($image, $width, $height): void
     {
         // Enable alpha blending and preserve alpha channel
         imagealphablending($image, false);
@@ -125,7 +125,6 @@ class imageProcessor
         $transparent = imagecolorallocatealpha($image, 0, 0, 0, 127);
         imagefilledrectangle($image, 0, 0, $width, $height, $transparent);
 
-        return $image;
     }
 
     private function resizeToFitRestrictions($mime, $width, $height)