The preferences window is way too complicated

[joss@…]

The preferences window would gain a lot from some serious cleanup. There are 3 major issues in it:

• Some preferences should be autodetected (e.g. there are some standard XDG methods to detect how to open a browser, a file navigator…)
• Advanced settings almost no one cares about are mixed with standard settings everyone needs to set. There needs to be a way to separate them; it can be a “Advanced settings” button in some sections that extends the dialog to the right with more settings, or another dialog for setting colors…
• Some preferences are completely useless, and the only purpose I can find them is to make the settings window look as if it came from MS Word.