feat: Speech synthesis alternative experiment [DO NOT MERGE]

[BenHenning]

The basics

• I validated my changes

The details

Resolves

Fixes

Proposed Changes

Attempt to demonstrate using the web speech API as an alternative for reading out labels instead of using a screen reader.

The mode can be activated using 'ctrl+alt+s' or 'command+alt+s'.

Some problems/limitations:

• There's a bit of a delay before speech utterance begins, but then it's consistent.
• Roles are not read correctly, so additional role context is ignored.
• This does not seem to work alongside a reader. I made some effort to try and make it so that elements are ignored when the speech synthesis mode is enabled, but this reveals two issues:
  • (1) The speech synthesis API seems to be completely disabled when a reader is enabled (at least for ChromeVox).
  • (2) Removing all ARIA information and event setting an element to 'presentation' does NOT stop its readout if it has a negative tabindex and is focused. Instead, the browser seems to fall back to some default accessibility node representation which then leads to an unhelpful readout (like 'Graphics Symbol' for a block's path object).

Reason for Changes

Test Coverage

Documentation

Additional Information

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