Subtle changes, bugs and feedback

That's one school of thought.
Another is to simplify interfaces by removing that which you cannot do, to not confuse users by offering options that are not available to them (in whatever the current context is).
It's the difference between a menu that says "These are choices you can make right now", and one that says "These are all the possible choices, but some of them are not available to you right now".
But anyway... I have work to do.

Mm, without wanting to get into a fussy UI/UX argument, I do think in the case of the pagination control it's currently rather confusing to show and hide the first/last button at the end based on current page context. A disabled button is a useful visual flag in that context. I've found myself having to scan left and read all the numbers to find the total number of pages indicator (which is much smaller, and grey) and working out what page I'm on and whether that's the penultimate one, and is the one to its right the last one or what. I know it's logical, it's just unexpected.

Might also benefit from some indicator like a double line or a gap to show where pages are skipped in the order. At the moment it's styled as a single button group when it might help to do it as a button 'toolbar' with small gaps to indicate non-consecutive pages.