That is a terrible article written by someone that it looks is paid by Microsoft to promote their mail client as every step they offer ends with a suggestion to migrate to outlook. All mail client has issue with connectivity and with hyperlinks. Mostly cause by antivirus programs.

Perhaps have a look at the Thunderbird support article which I think was the source of most of the article you found. https://support.mozilla.org/en-US/kb/hyperlinks-in-messages-not-working

To explain, Thunderbird takes the hyperlink and simply passes it to the operating system and basically says here is a link, I guess you know what to do with it. What you appear to be saying is your new laptop does not know what to do with those links or is being prevented from doing what it should. That immediately suggests an antivirus programs as they are one of the most common junkware programs preinstalled on new windows computers.

But it looks like you are using a Linux distribution of some sort, is it Ubuntu derived? Then it will be the sandbox that ubuntu places all applications in with their decision to use snap packages for applications. https://ubuntu.com/core/docs/security-and-sandboxing and https://snapcraft.io/docs/security-policies

Perhaps change packages or get a distro that does not offer to break your existing application on update.

Hello Matt,

Thank you for your answer. It was much simpler. The default browser was not set correctly. More precisely, I ran the command "xdg-settings get default-web-browser" in Terminal, and it returned firefox_firefox.desktop instead of firefox.desktop. I set it correctly using "xdg-settings set default-web-browser firefox.desktop", and it fixed the problem.

Best, Adrien