On the one hand, Github sorta works with our old browsers. On the other hand, it is now owned by Microsoft and a lot of developers don't like it and it seems gitlab is popular.
I started using Bitbucket because I needed something that supported Mercurial, and Bitbucket was one of the very few choices and it worked fine, though slow. Then Atlassian bought it. Things were mostly fine, then I couldn't upload builds of Mozilla anymore, even with Linux or falling back to their API and Curl. Then the worst was, with lots of notice, they not only dropped Mercurial support, but deleted everything. All my Mozilla repositories gone. I moved much of it and converted my Mercurial repositories to Git but it really left a bad taste in my mouth, they could have set everything to read only instead of deleting who knows how many repositories.
I also tried Sourceforge again with a test repository. They insisted on 2 factor login, which was fine, had an app on my phone and just had to copy a 4 digit number. Then I changed phones, didn't think of exporting the stuff from the 2 factor app and lost access to my account. Their response was nothing they could do, no way to reset things and the only way forward was to start over with a new account, which I never got around to.
My takeaway is that hosting services can't be trusted, especially using the free tier and the best thing is to have multiple repositories. One wonderful thing with Git (and Mercurial) is you have a copy of the whole repository locally. Hear of SVN servers going down and all the meta-data is gone. With Git, it is easy to clone everything and have backups.
With that in mind, Github works. Hopefully Martin has copies of all those repositories he has created.