It has already been reported : https://github.com/NodeBB/nodebb-theme-persona/issues/204
It is related to skin usage.
sorvani created this issue in NodeBB/nodebb-theme-persona
the profile menu is on the left
The topics thumbs using a link are not resized/cropped resulting in weird issues. Is this something normal (like to have big backgrounds) or an actual bug ?
I think that in ACP since you can enter a max value it should be cropped like when you upload the file.