When registering a custom QQuickImageProvider with the id 'camera' in the QML engine, an unexpected conflict arises if the Qt Multimedia module is imported in the QML file. This is due to the QMultimediaQuickModule internally registering an image provider with the same id 'camera' during its initialization (see multimedia_plugin.cpp).

As a result, when a custom image provider is registered with the 'camera' id, it gets destroyed as soon as Qt Multimedia is imported in the QML code, causing the application to crash. As long as Qt Multimiedia is not imported or different id is provided, everything is working as expected.

This behavior is undocumented and can cause confusion for developers integrating custom image providers with 'camera' id.