The option to save my theme changes doesn't work.

This is what I did: I enabled advanced options and injected some CSS. The theme changed and I clicked the save button. Another message pops up to ask if I want to save or save and publish. All good until now. However: both buttons do nothing, all changes are lost. If I try to change just some font and no CSS, the save button doesn't work either.

I really like this module btw. Keep up the good work. Temporarily solved my problem using the module CSS injector.