Opening Chrome always opens odd extra tab

I have a bit of an odd problem since a few days. Not sure if this is a problem with Chrome itself or with Plasma, or something else entirely.

Whenever Chrome is started - or whenever an external application wants to open a link -, Chrome does open/add the clicked link as a new tab.

But it ALSO opens a second new tab, with the following URL: “–password-store%3Dbasic”
It seems to me this is an argument for Chrome that somehow got garbled up and ended up being interpreted as a URL itself.

Obviously, I’d like to fix that behavior, but I have no idea where I would even look for where this extra argument is coming from.