What does it do?

Fix prepareSrcForThumb function. First check if src contain HTTP(S). If yes - return full url, if not - continue checking

Why is it needed?

Because right now first run checking, that check if file exist in filesystem.

try {
                if (!$this->filesystem->has($src)) {
                    return '';
                }
            } catch (Exception $e) {
                return '';
            }

But we check NOT file, but URL.
if (substr($src,0,4) != 'http') {
So first we should check file it is or url.

BEFORE

AFTER