Developer Login tries to open a browser…
→ Firefox is installed and working but no login page gets opened, even if I manually
start the Browser before opening sdkmanager
→ finally QR-login is recommended…
QR based Login requires an 8-digit PIN, that I cannot find anywhere…
Solved it by using the QR-based login:
Using the Phone didn’t work, as the browser didn’t enter the PIN provided within the QR-Code…
But copying the URL (link under the QR-image) and opening this in the browser did the trick: PIN gets filled out automatically and I could login via the browser…