Reading up on CSS stylesheet handling in Qt5, I found the following snippet at http://web.archive.org/web/20180629230221/http://www.qtcentre.org/threads/15119-QSlider-custom-handle-image-not-displayed :

I’m trying to set the height of the lines of a table. Namely, I’d like them to be significantly thicker. I’m aware that this can be achieved in the code, but how do I do that with a CSS I feed to the app (e.g., from an external file)?