Fixes #2919 Fixes #2673 Fixes #2641 Hide Youtube fixes

[keianhzo]

Fixes #2919 Fixes #2947 Fixes #2673 Hide YouTube overlays in immersive

[bluemarvin]

This PR seems to break auto immersive 360 video.

STR:

1. Click play on Mickey & Minnie's Runaway Railway
2. Click on fullscreen icon

Actual results:
Video goes fullscreen

Expected results:
Video goes into immersive 360 mode.

[bluemarvin]

This also doesn't seem to address #2673 as when I manually select a projection, it stays in that projection for the next video that is played.

[keianhzo]

@bluemarvin I Don't seem to be able to reproduce the fullscreen issue with the provided STRs.

Regarding:

This also doesn't seem to address #2673 as when I manually select a projection, it stays in that projection for the next video that is played.

AFAIK that's always been like that. We currently auto-select the projection based on a custom mozVideoProjection URL param that we append to the URL when the user plays the video, then we parse it when entering immersive video mode.
If another video is played while in immersive, we don't update the video projection. We could add webext communication to notify on the new playback start and send the projection parameter to update the projection mode.

[bluemarvin]

@bluemarvin I Don't seem to be able to reproduce the fullscreen issue with the provided STRs.

Regarding:

This also doesn't seem to address #2673 as when I manually select a projection, it stays in that projection for the next video that is played.

AFAIK that's always been like that. We currently auto-select the projection based on a custom mozVideoProjection URL param that we append to the URL when the user plays the video, then we parse it when entering immersive video mode.
If another video is played while in immersive, we don't update the video projection. We could add webext communication to notify on the new playback start and send the projection parameter to update the projection mode.

@keianhzo It has always been that way as far as I know. That's why I was not clear how this PR addresses #2673. If we don't plan to address it, we should close with a won't fix tag. I'll review again to see if I can reproduce the issue I was seeing.

[bluemarvin]

I don't see any breakages but I'm not sure what this is fixing.

[keianhzo]

@bluemarvin I've updated I was missing a case and you were probably hitting it. I've also added a fix for a missing div in #2947