Add keyboard shortcuts to toggle player fullscreen

[btzr-io]

PR Checklist

Please check all that apply to this PR using "x":

• I have checked that this PR is not a duplicate of an existing PR (open, closed or merged)
• I have checked that this PR does not introduce a breaking change
• This PR introduces breaking changes and I have provided a detailed explanation below

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting)
• Refactoring (no functional changes)
• Documentation changes
• Other - Please describe:

Fixes

• Can't exit full-screen from embedded content with key F11 Can't exit full-screen from embedded content with key F11 #2514
• Toggle fullscreen when pressing f Toggle fullscreen when pressing f #2159
• Gap between video player and background Gap between video player and background #3025 ( unrelated )

[neb-b]

Thank you for the fixes. Can you add a changelog entry for this? And any other PR's you opened. You can add them all to this one if you want.

[tzarebczan]

@btzr-io as always, don't forget to send your work log so we can show you some appreciation. Also, will DM you the hacktoberfest shirt form.