I’m aware of the terminology issue in the UI, there is an open ticket on it—it’s “Unlink” at the moment—and that ticket also refers to the missing contextual menu commands. I had removed most mention of them from the manual since it doesn’t seem like they’ll be able to fix that before launch, but I missed the spot you found. So thanks for the note on that, it’ll be removed from the next revision.
As for the rest, are you sure that the link wasn’t actually removed? In particular, note the yellow tip box right below the checklist you found, which explains how some browsers put text formatting on type of hyperlinks that the link removal command naturally will not touch.
That said, there does appear to be a bug with removing multiple links at once. I had no issues right-click on individual links and using “Unlink”, though. Maybe that is what you were running into, particularly since you make reference to lines whole lines of links.
Not sure what that is in reference to, sorry. I can’t think of any commands that would be phrased like that, since a URL isn’t really technically a link.
P.S. I’ve split this to a new thread, as it seems to be a bug report/query about something unrelated to a discussion on the effective gathering of research PDFs in a project.