Consider using IBus semantic preedit hints

[ftake]

Description

Under Wayland session, the current converting text segment is not highlighted. So users cannot understand which text segment they are converting.

Steps to reproduce

Steps to reproduce the behavior:

1. Type 'watashinonamaeha'
2. Press Space

Expected behavior

A converting text segment is highlighted.

Actual behavior

No text highlight.

Screenshots

See above

Version or commit-id

Mozc-2.32.5981.102+24.11.oss

Environment

• OS: openSUSE Leap 16.0
• IMF (for Linux): IBus
• Related Applications: Kate

Investigations

Additional context

A patch to fix this problem is ready for PR.

[yukawa]

Thank you for the report. I changed the issue title as what your #1485 is proposing is no more or less than just starting using IBus semantic preedit hints that are available since IBus 1.5.33. I think "Consider using IBus semantic preedit hints" would be more accurate if your goal is to submit #1485.

My point is that it's still possible that the text segment is not highlighted even after submitting your #1485 depending on the target application and other libraries such as IBus / GTK / Qt / Chromium, and so on. Hopefully the new issue title would make it clear that using the new APIs is what Mozc can do at best, and what the user would see is still not fully guaranteed.