Here's what I've tried, so far without success:"sudo add-app-repository http://oldarchive.trisquel.info/trisquel/pool/main/k/kompozer/";
That "took" OK, but subsequently, "sudo apt-get install kompozer" failed. Couldn't find the kompozer package.
Evidently, http://oldarchive.trisquel.info/trisquel/pool/main/k/kompozer/ isn't a repository, even though it's legitimately part of trisquel.info.
