When the extension displays the about page, it does so in a popUp box. This popUp box needs room on the screen. Usually this popUp box is quite small.
@matznerd's page wouldn't load sometimes because his comment was basically centered on my screen. There wasn't enough space to create the popUp box needed to display his larger about page profile.
When I scrolled the page - pushing @matznerd's comment to the top of my screen - the extension would load his about page instantly - in a super large (centered) popUp box.
@some_furry never loaded because (1) his comment was too low on the page (not enough room to generate the very large centered popUp box) and (2) his about page was too many lines. @some_furry's about page was never going to load because there was never going to be enough space on the screen to generate the popUp box.
The blinking "Loading..." was not that it was trying to retrieve the about page. Retrieving the about page was never the issue. It was trying to generate the popUp box and failing. Each time it failed, we would see "Loading..." again - which is why it kept blinking.