I compiled my binary from the latest master branch. I have noticed that the program has no problem displaying files that contain URL encoded % string such as %20 for space, but it is unable to move them to the trash. I get the error in the title. If I navigate to the file, I can delete it manually
I am using Whonix 17, updated last month. It is the XFCE version. It is being run in a VM, although I doubt that makes a difference. Let me know if you need more information.