There is a data loss issue with the browser.bookmarks.update() WebExtension API. At the moment there is no way to update bookmark tags, that's bug 1225916, so this bug is not about adding support for bookmark tags. But if you call browser.bookmarks.update() and update the URL of a bookmark all bookmark tags will be deleted! This does not happen if you only update the title of a bookmark. It was already reported in the issues tracker of one of my add-ons with Firefox 55 (https://github.com/cadeyrn/bookmarks-organizer/issues/47) and I can reproduce the issue with Firefox Nightly 60. I attached my add-on so you can test: STR: 1. create a bookmark, for example with http://www.mozilla.org (not with https://) and set tags for this bookmark 2. open the interface of the add-on and start the check for broken bookmarks 3. The add-on will find the created bookmark and show it as warning because of the redirect to https:// 4. Either click the link to repair the redirect or edit the bookmark manually in the add-on interface and change the URL Expected: All bookmark tags are still there Actual: All bookmark taags are deleted!

Marco, wondering if you have any idea about the cause on this. The webextension api simply calls PlacesUtils.bookmarks.update({guid, url}), we're not doing anything to remove or preserve tags.

Tags are bound to the url, when you change the url you're not exactly losing tags, those are still related to the old url. It's possible we'll change this behavior when we fix bug 424160, that's TBD though. The fact is, suppose you have 2 bookmarks pointing to the same url, both share the same tag. You change url of one of them. 1. If we leave the tags on the old url, the modified bookmark will apparently have lost tags 2. If we move tags to the new url, the unmodified bookmark will apparently lose tags An alternative may be to copy tags over so they apply to both old and new urls.