A while ago I made a bookmark add-on which could be used to do something similar. But it sunk without a trace on HN. Posting it here as readers probably already interested in bookmark related stuff...
for what it's worth i think it's pretty cool. if i understand right i can use it for example to change all links from dead site to archive.org, or from youtube.com to my favorite invidious instance.
(i also echo your sentiment that JS is deeply flawed :))
I submitted a "Show HN" post recently and watched it sink down the "new" page without any interaction.
I wonder if it's because I created a new account to post it, or more likely I had a terrible/generic sounding post title.
It's also difficult to pick the right time of day to post. I thought I had it right - picking Monday morning west coast (US) time, but I guess there is a big difference between just before and just after people get to work!
I would have liked to hear what people think, even if it's "This is bad, and you should feel bad".
/newest is a firehose, so timing is important. You have to submit at just the right time so that the users who are interested in your Show HN happen to be looking at /newest at that exact time.
https://addons.mozilla.org/en-US/firefox/addon/bookmark-cont...
Not being updated any more, but might be useful to someone.