Don't break dashboard if widget is no longer available
If a PHP Class for a widget does no longer exist, the whole dashboard breaks.
An example would be:
( ! ) Fatal error: Class 'TYPO3\CMS\Dashboard\Widgets\AbstractDoughnutChartWidget' not found in htdocs/typo3conf/ext/styleguide/Classes/Widgets/Pages.php on line 32
This widget extends the AbstractDoughnutChartWidget, which no longer exists, as I've removed the cherry picked patch. I guess the same behaviour would happen once an extension is removed from the system, which provided a widget that was added to a dashboard.
Updated by Daniel Siepmann about 1 year ago
Looks like unavailable widget classes is already handled, but extending a no longer existing class is not. Not sure whether this can be handled, or whether we can ignore this situation.
The only situation I can imagine would be an extension providing further abstracts. But if another extension relies on that one, it should add the dependency. So I would vote to close this issue I guess.