Krzysztof,
Please STOP touching the icon code and icons.
You have been ignoring the problems others are seeing, have ignored the information provided to you on them, and have been breaking existing functionality.
It is clear that you don't understand the aspects that are tripping you up (since I don't believe you're being malicious about it), but you are causing serious regressions in behavior. I've also have had to spend a lot of time unbreaking things that I otherwise need to be able to finish some of the new work I had been adding.
Also could you *PLEASE* complete the list of icon renamings that I've asked you for. We need this for compatibility, including needing to use it in some icon.cpp code that you removed yesterday. But the list of name changes is very important to document.
In case you're just stuck, I've gotten a start added under src/widgets/mappings.xml
Please get that updated with all the changes you've made. Thanks.