[Bug] Webpage shows empty toolbar space at the bottom after exiting fullscreen

[Mugurell]

Steps to reproduce

• Have the toolbar set as dynamic and placed at the top
• Open a video in fullscreen from a fullscreen webpage (eg: https://www.w3schools.com/html/tryit.asp?filename=tryhtml5_video)
• Exit fullscreen using either the fullscreen button, either the back button

Expected behavior

• The webpage should be displayed the same as before putting the video in fullscreen

Actual behavior

Browser shows a bottom margin - the size of the toolbar.

[video showing the bug on 85.1.1 Release]

FullscreenVideoShowsBottomMargin.mp4

Device information

The issue is reproducing on all current releases, 85, 86, 87.

┆Issue is synchronized with this Jira Task

[Mugurell]

I think this will be resolved by #17899
Linking the two to check this also after the other's ticket PR lands.

[stale]

See: #17373 This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.