[Bug] Wrong thumbnail after restoring backup

[aoba-seragakii]

Device information

• Suwayomi-Server version: v1.1.1-r1600
• Server Operating System: Windows 11
• Server Desktop Environment: N/A
• Server JVM version: Java 8
• Client Operating System: Windows 11
• Client Web Browser: Opera

Steps to reproduce

1. Restore backup from mihon or fork (in my case, restored from a TachiSY fork
2. Check some thumbnails

Expected behavior

The thumbnails should be correct

Actual behavior

Thumbnails are actually messed up (some of them), even though in the fork I'm using they are being displayed correctly
It's getting thumbnails from other manga in the library

Other details

Thumbnail in suwayomi

actual thumbnail

[Robonau]

delete the thumbnails folder (in the data/downloads folder)
and
clear browser cache

[aoba-seragakii]

delete the thumbnails folder (in the data/downloads folder) and clear browser cache

I did that and it didn't work...

[Robonau]

that's all the places those images are stored.