Apparently someething has been fixed remotely because now on the desktop version (121) I can see and use disqus in the commet section and I didn't change anything on my settings.The problem persist on the mobile version.
I can confirm that the new version of firefox won't load disqus. Also the new mobile stable version won't load it, and the beta mobile version is some week that does not load disqus anymore, so it is some new 'feature' in the current stable release ...