Hi Tod,
Thanks for the great work on this keyboard, I think I've been using it since having a Galaxy S2 and really can't deal with anything else.
I've just come across one issue which doesn't actually seem to be the fault of the keyboard, but is either due to Chrome or some crappy javascript and happens to only show up for this keyboard and not Gboard.
A vbulletin website I use has updated and now has some weird stuff going on with their 'post' and 'reply' fields. For example, if you make a 'new post' and enter a single newline (press enter) you then have to press backspace six times to delete the newline character, however 'select all' shows that the text field contains only one single newline...
On that website if you want to delete a bunch of text using gboard you just hold down backspace and the characters are erased as usual.
If you do the same in nextapp you find text being re-added and deleted, re-added and deleted - like, if you're backspacing through the word 'excellence' you may find the next press of the backspace key inserts the entire word minus the last letter. Basically, whatever is in the 'suggestion' window may get inserted when you press backspace.
From playing around it I am coming to understand how the android keyboard system works, the keyboard receives the full contents of the text field from the app? So if the app then changes the text field itself (i.e. due to javascript) there is a period during which changes made by the keyboard will be lost, because the keyboard will be sent a new field... right? That's what seems to be happening anyway.
Gboard seems to avoid issues by not updating the 'suggestions' field with backspace held down.
I don't think this is really your bug to solve, but if performance would be improved by following the gboard lead and not updating suggestions and re-polling the text field while backspacing, that might be worth doing?