No longer works with a Skype video call

[nox-machina]

Used to work with Skype until a few days ago where the video feed could be opened in PIP, but this is no longer the case.

[beaufortfrancois]

From what I can see, it seems like Skype now marks the video with disablepictureinpicture which tells the browser (and the extension) that it should not go in PiP.

[stephtr]

Any chance in #62 getting merged, since that would fix the issue for this and a few other websites?