This should simplify things regarding different styles on different states of the button, LTR/RTL icons etc.
Note: I am thinking of making those arrows framed OOjs UI ButtonWidgets with next/previous icons. This would affect the existing UI at least in a following way:
- icons will be slightly smaller than existing ones. See 'next' and 'previous' icons here: https://doc.wikimedia.org/oojs-ui/master/demos/#icons-mediawiki-ltr and https://doc.wikimedia.org/oojs-ui/master/demos/#icons-mediawiki-rtl. This icons are RTL-compliant (ie. they flip depending on what direction user is using). Possible alternative, ie. icons 'caretLast' and 'caretNext' does not seem RTL-friendly looking at those demo pages, so I would go with 'next' and 'previous'
- border around buttons will be thinner (one pixel instead of two)
- (most significant difference) disabled arrows will look like disabled button, as e.g. disabled ones here: https://doc.wikimedia.org/oojs-ui/master/demos/#widgets-mediawiki-ltr (slightly darker grey than now, white icon instead of black one)
Personally I don't consider those changes bad or good. Would still like to hear "OK" or "That's no good" from someone else, so pinging @Jan_Dittrich and @Lea_WMDE