* Fix issues detected by Knip
Including cleaning up some unused code and dependencies, using a React hook that we unintentionally stopped using, and also adding some previously undeclared dependencies.
* Replace remaining React ARIA components with Compound components
* fix button position
* disable scrollbars to resolve overlapping button
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Co-authored-by: Timo <toger5@hotmail.de>
This is an Element project (in the vector-im repo) so the Copyright
should be for New Vector: it was incorrectly attributed to the
foundation for some files (and some files were missing headers).
