Describe the problem you’re having:
Subscribe to feeds with YouTube iframe embedded, such as:
Which is displayed correctly in browser with all iframe player loaded.
However, on RSS readers such as tiny Reader RSS, Reeder 4 (both mac/ios), those iframes seem to be sanitized.
API request captured using tiny Reader RSS:
In content the iframe was removed.
<iframe id="ytplayer" type="text/html" width="640" height="360" src="https://www.youtube.com/embed/7HldRlTZj_g" frameborder="0" allowfullscreen></iframe>
My understanding is that it should be retained since youtube is whitelisted in functions.php during the sanitization.
tt-rss version (f38a89a131)
PHP 7.2.18, Debian 9.8, postgres 10.8