The image disappears when the parent of the weight setting is selected first.
If you select the sub-bones during weight setting first, the image will not disappear.
This has occurred since the 3.8.82 version was deployed.
It hasn't been seen since we upgraded to version 3.8.83, but I'm attaching it just in case. When the mesh image was replaced with another image, the image disappeared when the 'mesh' of the image properties at the bottom of the treeview was turned off.
I wrote it using a translator because my English is not good. Thank you.