Mandarin (Pinyin) IME input in table cells corrupts text and leaks into the row below

Environment: (MacBook Air M5, macOS 26.5.2, Capacities v1.67.3, Electron/Chrome v146.0.7680.216, en-gb Asia/Brunei UTC+8)

Steps to reproduce:

1. Switch to Mandarin (Pinyin) input method.
2. In a table cell, type English letters followed by Chinese via Pinyin composition — e.g. type "mvp", then continue typing pinyin to compose "能做，也可以使用".
3. Watch the cell and the empty row directly below it while typing.

Actual result:

• The typed text gets corrupted — "mvp" became "mvpai" (extra characters inserted mid-word) instead of staying as typed.
• The in-progress text also leaks into the empty row below the one being edited — that row ends up with a stray "mvpai" even though it was never clicked into or typed in.
• Reproduced this twice; same corruption + leak both times.

Attached: GIF recording of the bug, plus a screenshot of the final corrupted state (row 2 shows "mvpai能做，也可以使用", row 3 below it shows a stray "mvpai" that was never typed there).

*extra: after click Submit Ticket, and login, the attachment will disappear.