Firefox for Android Support Forum

I use the mobile version of Mozilla firefox and it choose to "remove" the open in other app feature for certain apps.

If I open youtube.com mozilla would ask to "open in other app" as an option instead of just opening it in the browser, youtube, twitter/X, reddit, etc. are fine, but for certain apps such as Pixiv and Patreon the option just dissapeared entirely, not even in the tripple dots at the bottom right does this option appear, can anyone help?

When commenting on 9gag, the blue "post" button disappears. If I choose "Desktop sight", the entire page reformats and becomes different and I lose all of my posting information.