Password Reset Link contains invalid characters

For troubleshooting questions, please post in the following format:

The URL sent in password reset emails contains invalid characters.

Steps to reproduce
Password reset flow

Expected behavior
Receive password reset link:

Observed behavior
Received password link:

Hi @barnops and welcome to the Mattermost forums!

Can you confirm that the value for your SiteUrl (either in config.json or in the environment variable MM_SERVICESETTINGS_SITEURL in your .env file if you’re using docker) does not contain this character in the domainname? %5C is the ascii hex code for a \ character, please have a look at your settings.