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Area

authentication

Describe the bug

I can see a ModelDuplicateException caused by a unique constraint violation (stacktrace.txt) after a user has been deleted.

Version

26.2.4

Regression

• The issue is a regression

Expected behavior

• next login with an unrelated user is successful

Actual behavior

• next login fails with status code 500

How to Reproduce?

• A user with an active session deletes themselves and then logs out (back channel logout)
• The browser is redirected to the login page again
• Another unrelated user attempts to log in through this login page and receives an error with status code 500 and said ModelDuplicateException

Anything else?

• We use a derived login theme and the double-submit prevention change (cc4691a) has already been implemented in our login form
• We use an external user storage implementation; cache is disabled there
• Might be related Duplicate Key Violation When Reauthenticating After Account Deletion via Google #38671