Please register a square image as the cover for the manual.
The thumbnail image is created from the cover image as follows:
- Square image - Scaled to 152x152 pixels
- Non-square image - Cropped to a square and then scaled to 152x152 pixels
Using a square image will prevent the left/right or top/bottom from being cut off.
Related：
Replace/Delete Registered Images and Videos (Web Browser Version)
https://teachme.jp/8/manuals/8080589
Replace Registered Images and Videos (iOS)
https://teachme.jp/8/manuals/42393629
Replace Registered Images and Videos (Android)
https://teachme.jp/8/manuals/42394575