I've also seen this behavior when trying to use Jira in Firefox. It's been a few months, but I was pretty certain it was because I had third-party cookies disabled.

Try disabling referrer spoofing; it helped for me.

What are the bug reports on uMatrix for this?

Don't really know what's going on with this. Now when I just disable uMatrix and ublock origin, I still get that redirect loop and I'm just not able to use Jira/Confluence. Luckily I don't need to use these products that often, so when I read something I just use our Slack bot to see the ticket.

I guess this may happen if browser doesn't accept third-party cookies.

what will you replace Confluence with?

We'll change our whole business model and do 100% open source, so I guess it'll be Github.

You mean GitLab?

GitHub is free, but definitely not open source (and has never pretended to be).

Github is 100% open source. News to me.

I believe he meant their product will be open-sourced so it will have home at github.

We use confluence for internal documentation that we wouldnt want public. Can that be done with Github or is your confluence used for public documentation?

Phabricator is a reasonable alternative for tasks, repos, CI, and a simple wiki. Not as polished on the wiki side as confluence but overall a good free alternative to Atlassian.