Preach.
I've also encountered a text entering latency issue with Safari Technology preview release 243, where I will be typing and then SECONDS will pass, with no text input. Not buffered either, just key strokes are completely ignored.
I filed Feedback.
I thought maybe it was fixed in Release 244 (WebKit 22625.1.17.19.1)? Yet exploring that more and encountering the same bug this morning, confirmed it's still there. So friggin annoying.
Good thing I have other browsers!
