Feature: #86880 - Enable password view at backend login

See forge#86880


On clicking, the TYPO3 backend login now displays an additional button to reveal the user's password, once something has been typed in the password field.


A user who is about to log in to the backend is now able to reveal the typed password. Once the password field is cleared, the visibility mode automatically switches back to its default to avoid revealing sensitive data by accident.


Revealing login credentials is always a security risk. Please use this feature with caution when nobody can watch your input, either remotely or by looking over your shoulders!