Mailspring inserting redirects into links in messages - how to prevent this?

Hi,
when sending a message, MailSpring is inserting text and changing the url of any link in the body of the message. This is regardless of whether the url is typed directly into the body or the ‘Add link’ button/feature is used.
Here is what Mailspring (on Linux) is inserting in links in email messages:
https://link.getmailspring.com/link/E1F3C0BF-4B8F-4BFA-A344-010B681DF59C@getmailspring.com/0?redirect=https%
Edit: this is inserted during sending without any warning or option to disable it and only visible once sent.
Any idea how to prevent or turn off this behaviour?
This is breaking the links and generating server errors when the recipient clicks the links.
Mailspring version is 1.15.0 on Linux (Mint).
Thanks