[Kindle NT] Full screen refresh doesn't work

[mergen3107]

• KOReader version: 2024.07-285-gfd3727274 (legacy)
• Device: Kindle 4 Non-Touch (FW 4.1.4)

Issue

Full screen refresh doesn't work, as reported here: https://github.com/koreader/koreader/pull/12484#issuecomment-2422787161

Steps to reproduce

Assign a hotkey to refresh the screen. Use it to refresh - nothing happens.

Well, I found that it sometimes works, but cannot trace the lead. See crash.log below.

crash.log (if applicable)

crash_partial.log.txt In this one, I did:

1. Use hotkey to refresh (1) - nothing
2. Jump back to previous chapter using Dpad left.
3. Use hotkey to refresh (2) - nothing
4. Use hotkey to refresh again (3) - it refreshed!
5. (outside crash.log Use hotkey to refresh n more time - nothing.

Although, logs looks exactly the same for all three refreshes above. Need some more debugging...