Portlet 3.0 Control Panel Apps cause unexpected errors

Issue

Following the deployment of a Portlet 3.0 Control Panel App, other areas of the control panel are experiencing malfunctions.
For instance, the My Sites selector is not responding, and in version 7.3, the Global Menu at the top is also inoperative, resulting in these error:
```
UnsupportedOperationException: Requires 3.0 opt-in
```

This error indicates a compatibility issue between your custom development (configured with javax.portlet.version=3.0) and the Liferay DXP 7.2/7.3 Control Panel.
While your custom development may work correctly on its own, the chain of requests triggered when accessing 'My Sites' or the Global menu (and potentially other areas) forces other components to conform to the same Portlet 3.0 specification level. Since this is not the case, it eventually results in the aforementioned exception.
Therefore, the only feasible workaround is to review your development to identify and modify any dependencies on Portlet 3.0-specific APIs, and adapt it to use Portlet 2.0 instead.