Fixes part of RaspberryPiFoundation/blockly#3370 Fixes part of RaspberryPiFoundation/blockly#9283 This PR introduces the plugin corresponding changes needed by RaspberryPiFoundation/blockly#9280. In particular, this: - Introduces CI workflow updates so that "tip-of-tree" is redefined as the corresponding experimental branch in core for screen reader support (to ensure CI passes here for changes that happen there). - Removes some access error overrides since the corresponding field was made public in the core PR (which is the root of the CI failures here). - Introduces some general instructions in the navigation plugin playground for folks testing Blockly with a screen reader (and points to RaspberryPiFoundation#673 for discussion). **Important**: Note that this PR's changes will NOT be merged into the `main` branch as-is. They will be reconsidered entirely (and likely largely reimplemented) separately from this experimental branch and submitted as a separate, future review for `main`. See RaspberryPiFoundation/blockly#9280 and Fixes part of RaspberryPiFoundation/blockly#9283 for more specifics on why the separate branch thing is being set up this way.

Commits

Commits on Aug 6, 2025

feat: Deploy GH pages w/ screen reader experiment.

fix: Use correct branch for plugin.

Commits on Aug 11, 2025

feat: Introduce initial screen reader support (experimental) (#684)

Merge branch 'add-screen-reader-support-experimental' into update-gh-pages-deployment-for-screen-reader-experiment