I got a fairly consistent repro. You need to scroll up and down multiples times after reaching the end of the page while the loading indicator is showing.
I didn’t dig the code yet, it might be related to 429 or just debouncing. The cases where you have it “naturally” are probably due to a specific size of the window which might create this loop of reached bottom/didn’t reach/reached bottom/didn’t reach…
We might look at this at some point; but this is fairly low priority.