User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.159 Safari/537.36

Steps to reproduce:

Hello,
Sorry if this report lack of some info, I'm not used too.
Redirection links aren't converted normally, the ones I've try seems to not been safelink generated by MS-office (tested on https://www.o365atp.com)
My version : 91.1.0 (64 bits) on Windows 10
-> Tested on Osx catalina & ubuntu 21.04 with same result

In a mail I have this link
http://t.e-sante.fr/c/1eG9W3?p=5&u=EWdlrr&n=EYowe6&cp=3&mta=pmta

Actual results:

TB open the link witheout converting it normally, on other web client the link is converted (like apple mail, office etc)

Expected results:

https://www.e-sante.fr/ce-que-vos-jambes-peuvent-reveler-de-votre-sante/actualite/615168?xtor=ES-92-%5BEsante_Alerte_Info%5D-20210910-%5BtestA%5D&tgu=EWdlrr

This is the redirected link (given from webmail on my phone)

I don't understand what you're reporting. Thunderbird will pass whatever link is in the source over to the browser, which will resolve it and the page thereafter can redirect if it's set up to do so.

(In reply to Magnus Melin [:mkmelin] from comment #1)

I don't understand what you're reporting. Thunderbird will pass whatever link is in the source over to the browser, which will resolve it and the page thereafter can redirect if it's set up to do so.

I assume it's some of security who male impossible the conversion. Any idea of what I've to do to auto convert theses kind of link ?

Thunderbird doesn't change the link. I doubt the browser does either. Whatever happens after that is up to the sites in question.