Android GBoard double space sometimes recognized as backspace.

[lishid]

Pressing space twice in a row sometimes inserts a space and then deletes it.
I believe GBoard does a special switcheroo for double space to become . (period+space) after a word.

Screen_Recording_20220113-133133_Chrome.mp4

[lishid]

Ok a bit further debugging info:

Gboard's double-space behavior causes a beforeinput to be fired with inputType='deleteContentBackward' which gets recognized as a Backspace key, causing cm6 to ignore the underlying DOM change and performing a backspace instead.

[lishid]

I've received reports that this happens with SwiftKey as well. It seems that SwiftKey "goes back", adds some characters. This causes cm6 to recognize the whole thing as a backspace only.

[marijnh]

Attached patch seems to avoid this. What was happening is that on double-space-tap, the second space caused a backspace beforeinput event to be fired, the first space to be removed again, and a period and a space to be inserted instead. That caused CodeMirror to just replace the whole mess with a simulated backspace key event (due to workarounds for other broken backspace behavior).