Content synchronization error when co-editing with Korean IME.

[weiQuill]

Please save me some time and use the following template. In 90% of all issues I can't reproduce the problem because I don't know what exactly you are doing, in which environment, or which y-* version is responsible. Just use the following template even if you think the problem is obvious.

Checklist

• Are you reporting a bug? Use github issues for bug reports and feature requests. For general questions, please use https://discuss.yjs.dev/
• Try to report your issue in the correct repository. Yjs consists of many modules. When in doubt, report it to https://github.com/yjs/yjs/issues/

Describe the bug
I ran the y-quill demo locally and opened two windows to simulate different clients. When I used Korean IME to quickly type in one of the windows, and then clicked on a line in the other window and tried to continue typing there, the error occurred.

The strange thing is that I can't reproduce this issue in the online demo.

Since y-webrt didn’t work for me, I just replaced it with y-websocket. Same as the online demo.

To Reproduce
Steps to reproduce the behavior:

1. Run y-quill demo locally.
2. Open the demo in 2 windows.
3. Switch to a Korean IME, I used 3-Set Korean.
4. Create some empty lines in the editor.
5. Focus into the first line of the editor in window A.
6. Press and hold T key.
7. Click into another line of the editor in window B.
8. Content synchronization error, the content on both sides is different.

Expected behavior
The content is synced correctly.

Screenshots

Screen.Recording.2024-08-28.at.15.24.59.mov

Environment Information

• Browser / Node.js [e.g. Chrome, Firefox, Node.js]
• Yjs version and the versions of the y-* modules you are using [e.g. yjs v13.0.1, y-webrtc v1.2.1]. Use npm ls yjs to find out the exact version you are using.

Additional context
BTW, this is also an issue that occurs when using Korean IME in my project, which is also a combination of quill+yjs.

• I'm a sponsor 💖
• This issue is a blocker for my project.

[weiQuill]

@ViniciusSCG Thanks for your quick reply, can you explain it more clearly?

[dmonad]

Hi @weiQuill

The last comment was a phishing attack by a random user. I hope you didn't download anything.

These kinds of issues are extremely hard to debug for me. Are you saying that the demo (https://demos.yjs.dev/quill/quill.html) is working but the demo in this repository (npm run demo) is not?

If that's the case, then this might be an issue with the quill editor version.

To verify events that we receive from the quill editor, could you modify the source-code of y-quill and add this logging statement?

   // line 104
    this._quillObserver = (eventType, delta, state, origin) => {
      console.log({ eventType, delta, state, origin }) // <--- add this line
     ...

It would really help me understand the problem. Thanks!

[weiQuill]

Yes, I didn't download those files, I was wary of downloading files, thanks for the heads up!

These kinds of issues are extremely hard to debug for me. Are you saying that the demo (demos.yjs.dev/quill/quill.html) is working but the demo in this repository (npm run demo) is not?

Yes, I just run the demo on my local with npm run start, and noticed the issue when testing.
Then I try to reproduce the issue the online demo(demos.yjs.dev/quill/quill.html), but it works fine there.

Thanks for pointing me in that direction, I'll give it a try!