You would need to cerate directory and file aswell for this. E.g. use touch and mkdir

the chrome diretory dont exist

As theres some problems using Firefox with dark themes. I may help with a partial improvement: This will make Textfields radiobuttons checkboxes, chats white background with black Text. (Partial fix.) The Problem is, that firefox apllys GTK colors and has its own static messed color design in the default theme. 1. Create -- (replace 'yourUsername' and number.default): /home/yourUsername/.mozilla/firefox/number.default/chrome/userContent.css 2. Copy and paste and Save this into the created file: /* ### SNIP ### */ textarea { background-color: white; color: black; -moz-appearance: !important; } input { border: 2px inset; background-color: white; color: black; -moz-appearance: none !important; } textarea { border: 2px inset white; background-color: white; color: black; -moz-appearance: none !important; } select { border: 2px inset white; background-color: white; color: black; -moz-appearance: none !important; } input[type="radio"], input[type="checkbox"] { border: 2px inset white ! important; background-color: white ! important; color: ThreeDFace ! important; -moz-appearance: none !important; } *|*::-moz-radio { background-color: white; -moz-appearance: none !important; } button, input[type="reset"], input[type="button"], input[type="submit"] { border: 2px outset; background-color: #eeeeee; color: black; -moz-appearance: none !important; } body { background-color: white; color: black; display: block; margin: 8px; -moz-appearance: none !important; } /* ### SNIP ### */