* Adjust font size slider range, it starts at 80% and ends at 180%
* Font size is always shown in percentage now
* Better handling of initial font size, it should now detect browser or site default correctly
* Use relative units
* Tweak styles
This is a part of the header refactor
* Add hover and active state for title button
* Clean up DOM structure
* Clean up unnessecary styles
* Clean up HTML class names
Users are unable to open the preference panel when there are no theme option saved in localStorage.
It is because prefValue.theme will return null which will stop the script from executing.
Now when prefValue.theme is null, it will default to auto.