I just check something because my memory as faults... Firebird was the name of Firefox and the mail client was called something like Mozilla mail or something else.

It was originally Minotaur (when the browser was Phoenix), then they were Firebird and Thunderbird, until the browser renamed to avoid a name clash.

I really don't remember (+quick check) Firebird for the email client, do you have source for this?

Predecessor of Firefox was Firebird, and before that it was even called Phoenix.

https://en.wikipedia.org/wiki/Firefox#Name_changes

So it wasn't used before Thunderbird, that was the point of OP and myself. We were talking about the email client(!).

And I was an user of firebird, the database.

No, the email client was never called Firebird, that isn't what I was saying.

Browser: Phoenix -> Firebird -> Firefox Mail client: Minotaur -> Thunderbird

Firebird was the browser's name, after phoenix and before rebranding to firefox.

So it wasn't used before Thunderbird, that was the point of OP and myself. We were talking about the email client(!).

And I was an user of firebird, the database.

Yes that is a confirmation.

Firebird was actually the database whose name they hijacked when they had access to AOL's legal army.

Also K9Mail is now Thunderbird for Android.

They didn't really hijacked anything. Firebird made sense coming from phoenix. It wasn't a good choice considering the database existed before but it wasn't really an hijack in the sense that both are significantly different product that trademarks wouldn't have clashed. It was just annoying when doing web searches (similarly to gemini the google AI product vs the protocol).

It wasn't that simple. I couldn't find Firebird's original position post but this is close enough.

https://www.mozillazine.org/articles/article3097.html

I’ve used it since it was called Netscape Mail. ;-)