Background image in layout not being shown

Hello!

I've just started working with MultiTerm Desktop 2021 and it won't show the background image for the layout we use by default with our termbase. This works without problems in MTD 2019. I've tried creating a new termbase with a new layout, changing the location of the jpg file, and more. Nothing works. I can change the background color, but any file I select won't be used. What happened?