Attempting to access the sign-in page for GitLab.com with Tor Browser gets stuck in a loop of anti-bot verification. Eventually it will prompt to click to verify user presence but afterwards it will loop and prompt again.
Tested with Tor Browser 13.0.11 and 13.5a5 on Linux x86_64.
Been attempting to communicate with GitLab support. However the response has been lacking. GitLab support does not provide ticket based support if you are either unable to register or are utilising a free tier account.
However they do provide a forum and I created a topic
To Tor Browser developers or those who understand the internals. Is it possible to disable the Cloudflare challenge being completed over the Cloudflare onion-service for troubleshooting?
This is a known issue with Cloudflare and/or GitLab with some browsers/privacy settings enabled.
I have exactly the same experience with my own GitLab account trying to access it using TB. I also have the same result using regular Firefox browser (115.11.0esr) proxied through tor and with pref privacy.resistFingerprinting set - see: /t/cant-open-the-signin-page-it-keeps-showing-checking-your-browser-before-accessing-gitlab-com/45857/8 on the GitLab forum page (sorry I’m not allowed to add more then 2 links in a comment here for some reason). Setting privacy.resistFingerprinting to false sometimes fixes the issue, but of course you can’t (shouldn’t!) do that in TB.
This behavior therefore does not seem to be Tor Browser specific, but it does seem to be specific to GitLab’s Cloudflare configuration and/or insistence on fingerprinting you before login (I have no such trouble elsewhere with the above configuration). I’d therefore be surprised if this was within the control of the TB devs’ GitLab account. GitLab themselves need to fix this and as a user, Tor Project themselves are ideally placed to pressure them to do so.