Something broke. I think there was no problem when I last visited a couple days ago. Today all posts have only a down arrow for the spillover actions, no icons. If I move the mouse above where the icons /should/ be, the pointer turns into a finger. So the actions are still available but just invisible.
(edit) when I use Firefox and enable displaying images, only then can I see icons. I normally use Ungoogled Chromium with images disabled (images dramatically increase my Internet costs). So I wonder if someone tried to get fancy and install images instead of icons from fonts.
Clear your browser cache, should fix it.
I cleared the cache and did a hard refresh (control-shift-R) and this makes no difference.
BTW, I am able to reply to you only by hovering over the area where I expect to find a reply button, and the mouseover text says reply.