Steps to replicate the issue (include links if applicable):

• Navigate to the login screen.
• Attempt to log in using a username and password stored in a password manager.
• Trigger autofill from the password manager.

What happens?:
The login process fails.

The user initially reported the error message:

"WebAuthn-Anmeldeinformationen wurden nicht gesendet"
("WebAuthn credentials were not sent")

The user later clarified that they are unable to log in even with a username and password.

According to the user's screen recording, the screen briefly turns black when the password manager appears to fill the credentials.

What should have happened instead?:
The app should allow users to log in successfully using username/password credentials.

Software version (on Special:Version page; skip for WMF-hosted wikis like Wikipedia):
Android app: 50586-r-2026-05-12
Device: Google Pixel 6
SDK: 36
Other information (browser name/version, screenshots, etc.):
User provided a screen recording: https://youtube.com/shorts/DejmCLC4khY
User uses a password manager.
User initially suspected a passkey/WebAuthn issue.