Security-related warnings after login
A TYPO3 integrator is responsible for the correct configuration of the TYPO3 system. Usually, an integrator has administrator privileges and logs in to the backend from time to time or regularly. If a user with administrator privileges accesses the system, TYPO3 triggers some basic system checks and shows an error or warning message in a box right after the login.
These checks are for example: administrator user name and password (e.g. does the user still use the default password?), Install Tool password, etc.
If you, as an TYPO3 integrator, should ever come across those warnings, react immediately and update the appropriate setting (e.g. change the password).