Been using KeePassX for sometime then informed of fresher repo in KeePassXC only recently. Spotted the old connector and had a sad it didn't work in Firefox Quantum. But now I has a happy!

Setup was pretty simple. Database had to be unlocked for the WebExtension to find it as a source but even my uncaffeinated brain managed it. Works a treat. Would prefer it locked via my Yubikey too and with Firefox rocking through U2F implementation https://wiki.mozilla.org/Security/CryptoEngineering your extension is a cornerstone of my workflow. Nice work!!!