Use HTTPS to connect to GitLab not SSH
While GitLab gives instructions for using SSH keys, this method does not work with gitlab.pavlovia.org.
Most users should be able to sync directly from PsychoPy Builder without needed to choose between HTTPS and SSH at all.
However, if you do need to make a choice, for example because you are cloning a repository, use HTTPS
If you have already cloned a repository using SSH, open the hidden
.git/config file within the project and replace all mentions of git@gitlab.pavlovia.org: with https://gitlab.pavlovia.org/ (or fetch the URL from GitLab site and paste the HTTPS URLs one-by-one.
If you have a reason why you cannot use HTTPS, please give details on the following thread.