Unable to log in or create manual activation file in Unity Hub

I'm running the latest version of the Unity Hub on Mint 17.3. When I attempt to log in, the login window opens, but is blank. I've heard it mentioned that this window is populated from a web view, so I've tried turning off my firewall; this had no effect. Furthermore, I've tried using the procedure to manually activate a license, but no matter what I've tried the license request file never gets created. Has anyone else experienced these issues and managed to fix either of them?