Rated 4 out of 5 stars

Depuis la dernière mise à jour presque tout les messages avec signature DKIM valide auparavant sont maintenant en alerte " La clé de signature non sécurisé (clé trop petite)"

Est ce un bug ou une nouvelle fonctionnalité ? Et comment faire "comme avant" ou avoir une meilleur clé

This review is for a previous version of the add-on (3.0.0). 

This is a new feature (Cryptographic Algorithm and Key Usage Update (RFC 8301)). But you can disable the warning, see https://github.com/lieser/dkim_verifier/issues/141#issuecomment-496317683 for details.

You can also try to report this to the sender, so that they update their key to a bigger one.

Next time please don't use the reviews to report problems. Use https://github.com/lieser/dkim_verifier/issues or write me an E-Mail (in English or German).
See also https://addons.thunderbird.net/en-US/review_guide