Passwords are not case sensitive in the desktop app. If your password is “password123” and you log in with caps lock on: “PASSWORD123”, your password is still accepted.
Reproduction Instructions:
Using a test account whose password contains Latin letters, log in to the Battle.net desktop app.
Log out
Turn the Caps Lock key on your keyboard on.
Log in to the test account using the same password (this time capitalized).
Confirm the login request is accepted.