I'm using Teams on Linux (1.3.00.16851 amd64 on ubuntu 20.04). The company I work for uses Citrix Netscalar to do authentication. When I start Teams I enter my company email address. I then get the netscalar login page (inside teams) and I login. After a successful login I get a call from microsoft authentication (as expected) and after pressing # on my phone, the default browser (firefox) is opened and the channels are visible in the browser. Inside the teams application the netscalar login is still visible (as if it is frozen).
The strange thing is, It worked fine last wednesday (july-8th) but since thursday (july-9th) this opening of the browser after login started happening.