Issue details
When marks are applied (e.g., “Bold” or “Underline”) while typing with a SouGou IME, Android devices seem to duplicate the characters after composition status is ended and new characters are input.
Steps to reproduce
- Go to the basic editor at ProseMirror basic example on broswer of android device.
- Enable IME’s prediction feature
- Put the cursor at the end of a “Bold” text in the editor
- Begin typing, e.g.. type a “y”
- Wait about 5s
- Type anything
ProseMirror version
1.33.8
Affected platforms
Android
Screenshots / Screencast (Optional)

Pre-analysis:
We found the below snippet in prosemirror-view/src/input.ts,so that makes sense why editor will exit composition after 5 seconds of inactivity on Android. What I’m curious is why there is no compositionend event fired?
const timeoutComposition = browser.android ? 5000 : -1