This tool is great!
I'm using the Linux version (tried on Manjaro and NEON) and I encountered an annoying bug. In KDE Pixelorama messes up the file associations of almost every file type, most of which are not even images. When trying to switch the file associations back to the preferred dedicated software, it doesn't work and it switches back. I have to manually remove Pixelorama from every file type association and it's awful to be honest. It does this for all the user profiles on the PC, and though I like having something to do in my spare time, fixing the file associations manually is not my preferred pastime. I think you should do something with this issue so that the new users wouldn't encounter this problem.