I noticed that it is impossible to get out of the code entry field when you have to rely on keyboard navigation. (Mediawiki 1.31). Would it be hard to fix this?
Topic on Extension talk:SyntaxHighlight
The issue is that the tab key is used to indent/outdent the code. I don’t think it would be hard to change this behavior to navigating between form fields, but then there was no way to change the indentation (except for copy-pasting the tabulator character or entering it by ASCII/Unicode codepoint, neither of them is convenient). So there’s no good solution for this; the developers seem to have chosen a solution that’s better for those who prefer indenting their code with tabs but worse for those who rely on keyboard navigation.
Could Shift+Tab be adapted for this purpose? AFAIK it has no special function within the field, and it also doesn't in the browser or OS (Ctrl+Tab switches between open tabs in Firefox and (IIRC) Chrome, and Alt+Tab switches between open program windows in Windows).
It has: that’s the outdent. (Shift, as usual, reverses the direction: here it’s outdent instead of indent, if it wasn’t overridden, it would go to the previous form field instead of the next one, Ctrl+Shift+Tab goes to the previous tab instead of the next one, Alt+Shift+Tab goes to the least recently used window instead of the most recently used one, and so on.)
Aah, right, I always forget about outdenting for some reason. So much for that idea, then.