feat: v1.1.0 pre-release QA based fixes #2276

[marek-mihok]

The PR fulfills these requirements: (check all the apply)

• It's submitted to the main branch.
• When resolving a specific issue, it's referenced in the PR's title (e.g. feat: Add a button #xxx, where "xxx" is the issue number).
• When resolving a specific issue, the PR description includes Closes #xxx, where "xxx" is the issue number.
• If changes were made to ui folder, unit tests (make test) still pass.
• New/updated tests are included

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This PR fixes several issues based on the v1.0.0 pre-release QA, namely:

• Audio annotator: Wrong annotator dimensions if Wave app is loaded when browser tab is not visible
• Audio annotator: In specific scenario user was able to activate empty tag and annotate with it
• Toolbar: Download prop example was not working due to link being from different origin.

TBD:

• Firefox "randomly" dropping Wave server connection since this commit. - Fixed by fix: Close websocket connections as per spec. #2278
• Audio annotator playback issues for several file formats when using Safari and/or Firefox. - TBD later as agreed.

Closes #2276

[mturoci]

LGTM!