Here’s what I found after some testing on the forum with a resized viewport to simulate mobile and DevTools: the reactions popup is definitely there. The element shows up and goes away as expected when hovering and removing the cursor. But for some reason, it does not appear on-screen. Or at least it seems to.
Well, here’s a screenshot when hovering:
If you look really closely at the area just above the bottom red line above the thumbs-up button, you can see a faint shadow, which is the popup. There’s simply no reactions on it. This occurs in safe mode.
I also cannot, for the life of me, simulate a hover on the button to make the popup stay, even on desktop, using the DevTools’ controls to toggle the state yields no results. I cannot, therefore, ascertain if the reaction’s divs are even there.
EDIT: The divs are definitely there:
As are the icons (they exist):
(And going to the URL shows the image)