[jasonmorton]

Not OP, but for me adding or deleting a character in the middle of a paragraph in a latex doc hangs for maybe .5s or more, often. This is a fairly new phenomenon, never happened 2+ years ago.

[taeric]

That sounds broken. :(

Good luck getting it fixed, if you are still trying. A basic profiler-start, type, profiler-stop, profiler-report can probably pay the blame easily.