Mail link redirect


I want to send the following link:

The link is redirected to:

What’s the purpose of this redirection?

When I try to open the link in an other e-mail-client I’m redirected to the nextcloud login page.
Only after logging in, I will be forwarded to Google.
Why must I login to get forwarded?

How can I completeley disable the rederection?

Thanks for your help :slightly_smiling_face: