I've tested for several times,that "Generate a Random Password" function don't generate a length of 12 ,but actually 11. When i change the length to 13,it works fine.

https://github.com/Coool/Browsers-Add-ons-keepass-macpass-helper

Best credentials (username, password, PIN) Add-on (Extension) for KeePass for my needs. Supports not only local machine, but any machine in your LAN. Recent changes supports KeePass built-in OTP - https://github.com/belaviyo/keepass-macpass-helper/issues/62.

I have experience with Add-ons (Extensions):

Active:
KeePassXC-Browser (based on chromeIPass and some changes merged also from KeePassHttp-Connector) - https://github.com/keepassxreboot/keepassxc-browser
ChromeKeePass - https://github.com/RoelVB/ChromeKeePass
KeeWeb Connect - https://github.com/keeweb/keeweb-connect
Keywi - https://github.com/LEDfan/keywi

Inactive:
KeePassHttp-Connector (forked from chromeIPass/passIFox) - https://github.com/smorks/keepasshttp-connector
PassIFox (for Mozilla Firefox), chromeIPass (for Google Chrome) - https://github.com/pfn/passifox

P.S.
Check out my collection of Privacy & Security add-ons - https://addons.mozilla.org/firefox/collections/17493519/Coool-Privacy-Security

Excelent plugin. Love it. Worked with one click.

Esperienza positiva da anni, molto comodo e efficente.

Works as expected, nice piece of work.

Works very nicely with MacPass on MacOS, easy to use and lightweight.

Great addon, works nearly flawlessly. If I could invoke it using a keyboard shortcut, it would be perfect. But I guess that's a restriction of the addon SDK for now...

une vrais application fonctionnant parfaitement avec Keepass logiciel professionnel , cette application respecte la confidentialité et vous permet de vous servir en toute simplicité de Keepass , je n'ai pas rencontré de problème , tant soi peu que vous ayez mis en place ce qu'il faut .

merci a l'ingenieurie d'avoir fait ce module.

Cool, also work with other Keepass alternative KeePassXC.

J'ai enfin trouvé l'extension qui me convient pour Keepass.
J'en avais marre de Keefox, beaucoup trop complexe, beaucoup trop lourd. Le passage à Firefox 57 a été l'occasion de chercher s'il y avait une web extension pour Keepass. Avec KeePassHelper Password Manager, on a une extension simple, qui s'installe sur tous les systèmes et tous les navigateurs, qui n'est pas entièrement "automatique" (il faut cliquer sur la zone du nom utilisateur ou du mot de passe, puis cliquer sur l'icône de l'extension), mais qui fonctionne dans tous les cas. Testée avec succès avec des débutants qui n'arrivaient pas à utiliser Keefox.

I'm not sure what went wrong in p4cm4n's review, but the option to save logins to the db appears when you right click the extension's button. The generation is there too. Overall its slightly less seamless than PassIFox was, but I suspect that is due to the nature of WebExtensions.

Very light, does not require restart, and identifies most sites.
Had some issues with the UI at first - the action buttons were not displaying at all at it was unclear how to use. The documentation contains the list of hotkeys, though.
It works fairly well, either standalone or supplementing KeeFox in finding sites that the other plugin misses.