remove important flags on default styles to enable base functionality of firefox

[pulpocaminante]

please, all the overrides / !importants make the web unusuable

overriding website styling is not particularly nostalgic either, because it makes every website incredibly ugly, even on neocities

9d8addb adds the addition environment variable QT_QPA_PLATFORM=xcb to the default config, ensuring that users who primarily use wayland DEs don't have QT problems