Keyboard shortcuts that use the access modifier don't work with VoiceOver

[afercia]

Splitting this out from #5694 see #10545

Gutenberg uses a convention for keyboard shortcuts where the access combination translates, on macOS, to Control Option. Currently, there are a few shortcuts that use this modifier, including the new Blocks navigation menu implemented in #10545.

Unfortunately, VoiceOver on macOS uses Control Option as its own default modifier so all the Gutenberg shortcuts that use Control Option either trigger a specific VoiceOver feature or don't work at all.

So far, I've found the following shortcuts using Control Option:

Display this help. ^ ⌥ H
Open the block navigation menu. ^ ⌥ O
Remove the selected block(s). ^ ⌥ Z
Remove a link. ^ ⌥ S
Add a strikethrough to the selected text. ^ ⌥ D
Display the selected text in a monospaced font. ^ ⌥ X
Add link ^ ⌥ a (undocumented in the Help Modal, alternative shortcut available)

Basically, all the shortcuts implemented with rawShortcut.access() or <Shortcut type="access" .... All of these need to be changed to use a different modifier.

Aside: still thinking the best path forward is a mechanism to allow users to re-map and customize shortcuts, as proposed in #3218.

[ellatrix]

So this is also an issue with the old editor? WordPress has used the "access" modifier since a long time, and it was hard to find anything that didn't clash with the OS or browser. Has this always been the same in VoiceOver?

[afercia]

Correct.
For example, testing with Safari + VoiceOver, Ctrl-Alt-{1-6} to change a heading level doesn't work.

[afercia]

See related core Trac ticket: https://core.trac.wordpress.org/ticket/39271

[afercia]

For reference: in the new WAI-ARIA Authoring Practices 1.1
there's a pretty good section dedicated to keyboard shortcuts. It's more about what not to do:
https://www.w3.org/TR/wai-aria-practices-1.1/#kbd_shortcuts_assigning

Among others, avoid:

macOS only: Control+Option + any combination of other keys.

[tbdalgaard]

Most of the issue here could be fixed if option was removed so the keystroke would be ctrl followed by the letter/number instead. That would solve the issues on Mac OS with Safari.