So far I haven’t perceived them as too large, but I don’t use a lot of add-ons that add their own buttons. After taking a good look at them now, I think you’re right. They feel a bit too big.
How the height and width of the buttons are calculated:
calc(var(--buttons-size) - 2px);
The variable --buttons-size is set to 2rem at the moment:
Maybe 1.85rem instead of 2rem would do the trick:
Like this you can fit two more buttons on one line at that same window width.
I wouldn’t go all the way to 1.8rem because then the icons get really small. One could reduce their padding of course, but that wouldn’t look great either.