The most likely explanation of the effect you're observing is that the server, having done a database fetch to get you the profile once, is not interested in doing it over and over again.
It's cached. You do not have a uniquely broken upvote button.
I've tested this many times by up-voting predictably stable comments, noting the karma number before and hours later. No effect. No exceptions. Additionally, there was a time where this limitation didn't exist. I am pretty sure I triggered a flag for my tendency to up-vote controversial and underdog content.
I don't think dang is right about everything, but I get the impression that he's honest and expect he'd confirm this limitation on my username. Ask. But I'm not grovelling for equal rights on HN and will make no inquiries to insiders.
Also, if your interpretation was correct, there's this really big parallel contrary reality where the upvote system works and entries are accepted and processed, hence the ever changing karma number of each active user. Perhaps it's the ad blocker, but it's not normal
But first, I loaded your profile.
Then I refreshed it several times.
At no point did your karma score change on your profile.
It's caching.
I once had this limitation on my own account. It was because I had upvoted certain grayed out comments that were flamewar fodder. I did that because there were equally bad counter-comments in the thread that weren't voted down (grayed), and out of a misguided commitment to balance I wanted to fight for the losing side.
When I emailed dang to ask about my voting limitation he explained why my account had been penalized. I said I wouldn't vote up bad comments in the future and he restored my comment voting. Now when bad arguments attract bad counter-arguments I just downvote instead of trying to boost the somewhat-less-bad side.
You don't have to send email about this if you don't want to, but it doesn't require groveling to fix.
I think some folks see the apparent simplicity of HN and assume it's primitive and clean, with nothing too sophisticated running in the background.
I haven't seen this in the reporting. Can you share any context for it?
They went up on an experimental spacecraft on its shakedown cruise. They’re coming down on a different spacecraft than planned — a different make of spacecraft, even. That’s never happened before, and is neither normal nor common. The spacecraft type they flew up will almost certainly never fly again because of how badly the shakedown went. That’s never happened before to a manned design to my knowledge — certainly not normal or common.