I’ve experienced quite the same issue:
After updating to version 3.5.2 (AppImage), I’ve once had to reauthorize my account (only one) again. And now, on every app start, I have to “manually” log in via web browser window. Password seems to be saved in keyring, so no need to enter password again. Reversion to version 3.5.1 fixed the issue and the client is behaving normally again. Something in 3.5.2 has definitely changed or is even broken.