The endpoint was removed by another team because apparently nobody was ever using it (barely any traffic in last 2 months). So people seem to be getting their browser information in a different way anyway.
In the future we are going to auto-collect this when you make your report so that you don’t have to copy-paste this. We already do this for the issues reported on documentation content (when using the feedback widget on the docs site) and we will do similar functionality as we introduce more bug reporting surfaces in the product itself.
For the time being it should be ok to just mention:
your browser + that you are on latest version of it
your OS
that you tested it doesn’t occur with all browser plugins disabled