gmail "next" failes when adding new e-mail account

Hi all, I'm trying to add another e-mail account to my Thunderbird. This is an account linked to gmail (the professional Gsuite+ type). Everything goes fine, until I get a pop-up screen with the gmail log-in screen. I have to click "next" (as you do when you're logging in on gmail) to move from my e-mail address to my password. The pop-up screen doesn't react, Thunderbird freezes, it autoshuts, and I cannot open it unless I restart by PC. I've already tried disabling all pop-up blockers in the browsers I use, but to no avail. It may be important to note that the pop-up screen doesn't open in my browser, but instead in Thunderbird itself.

Please help me- it's a pain to answer all e-mails on my phone. Thanks in advance!