Along those lines, I've been seriously considering switching to the FF ESR version (currently v 52.4), which will be supported until the release of v 59 next March. This way security patches will still be made available, but all my old "legacy" extensions will continue to work. (You can get it here: https://www.mozilla.org/en-US/firefox/o ... tions/all/
). Then I may also revert back to an older version of XM to get away from the continuing problems, although that won't resolve the recurring issues I (and others) have been having accessing bookmarks directly on the server through my.xmarks.com should the need arise.