Hide settings not functional on Firefox for Android

[WesleyBranton]

Firefox for Android does not support all CSS scrollbar customizations and features of the add-on. Options that are not available in Firefox for Android should be hidden.

During testing, I have noticed that the following functionality does not work on mobile, although further testing is needed to see if this is just specific to certain mobile devices:

• Scrollbar width can only be platform default or hidden. The thin option has no impact on mobile.
• Automatically hiding scrollbar does not work because Android does this already.
• Only the scrollbar track color can be set because the scrollbar thumb is always transparent.

As of right now, it appears that the following settings should be available on Firefox for Android:

• Scrollbar width
  • Platform default
  • Hidden
• Scrollbar track color