(Un)folding a 100+ comment subtree is kind of slow, don't you think?
I don't have any large such subtree at hand, but visiting large 200+ comment threads is really fast.
Out of curiosity, I just tested a 100-comment thread on my phone with Firefox. Folding it was instantaneous, unfolding it took ~4 seconds. That makes me wonder what takes so long, given that the initial page load didn't take anywhere near that long.
Tried it with a sub-tree of ~240 comments just now. Less than a second on Firefox. Perfectly usable and acceptable in my opinion. To me there are probably hundreds of more annoying or slower things currently out there on the web that frustrate me.
"Less than a second" is definitely not an acceptable metric for any kind of UI latency. It should be at most a frame FFS, and that means 8 milliseconds on today's screens.
Same experience on my Android phone. I just tried to unfold 75 comment, it has a noticeable latency in both chrome and firefox.
Same here, just this comment's tree starts to have some perceptible latency on my one+ 8 pro (which should be pretty powerful. In contrast I have some Qt apps where unfolding trees with tens of thousands of nodes is instant.