Error Call to a member function getTimestamp()

[tobiasschaeferptb]

Hello,

When I click on an extension in the list of Available extensions for a client this error occurs for some extensions (not all):
Call to a member function getTimestamp() on null | Error thrown in file t3monitoring/vendor/t3monitor/t3monitoring/Classes/ViewHelpers/Format/DateTimeAgeViewHelper.php in line 29
My setup is TYPO3 13.4.22, t3monitoring 3.1.0, php 8.3.23.
The error only occurs with certain extensions, like backendtools, md_saml and news.
If I change Classes/ViewHelpers/Format/DateTimeAgeViewHelper.php (line 29) from:
return BackendUtility::dateTimeAge($date->getTimestamp(), 1, 'date');
to:
return $date ? BackendUtility::dateTimeAge($date->getTimestamp(), 1, 'date') : '';
it works.
It looks like there are some extensions with versions without a last updated date:

Greetings,
Tobias