Merge branch '8.4' into 9.0

# Conflicts:
#	Neos.ContentRepository/Classes/Domain/Repository/NodeDataRepository.php
#	Neos.Neos/Documentation/References/CommandReference.rst
#	Neos.Neos/Documentation/References/EelHelpersReference.rst
#	Neos.Neos/Documentation/References/FlowQueryOperationReference.rst
#	Neos.Neos/Documentation/References/Signals/ContentRepository.rst
#	Neos.Neos/Documentation/References/Signals/Flow.rst
#	Neos.Neos/Documentation/References/Signals/Media.rst
#	Neos.Neos/Documentation/References/Signals/Neos.rst
#	Neos.Neos/Documentation/References/Validators/Flow.rst
#	Neos.Neos/Documentation/References/Validators/Media.rst
#	Neos.Neos/Documentation/References/Validators/Party.rst
#	Neos.Neos/Documentation/References/ViewHelpers/ContentRepository.rst
#	Neos.Neos/Documentation/References/ViewHelpers/FluidAdaptor.rst
#	Neos.Neos/Documentation/References/ViewHelpers/Form.rst
#	Neos.Neos/Documentation/References/ViewHelpers/Fusion.rst
#	Neos.Neos/Documentation/References/ViewHelpers/Media.rst
#	Neos.Neos/Documentation/References/ViewHelpers/Neos.rst
#	Neos.Neos/Documentation/References/ViewHelpers/TYPO3Fluid.rst
#	Neos.Neos/Resources/Private/Translations/fi/Main.xlf
#	Neos.Neos/Resources/Private/Translations/fi/Modules.xlf
#	Neos.Neos/Resources/Private/Translations/nl/Modules.xlf

Author: kitsunet

Neos.Media/Classes/Domain/Service/ThumbnailService.php

@@ -255,7 +255,15 @@ public function getUriForThumbnail(ImageInterface $thumbnail): string
     {
         $resource = $thumbnail->getResource();
         if ($resource) {
-            return $this->resourceManager->getPublicPersistentResourceUri($resource);
+            $uri = $this->resourceManager->getPublicPersistentResourceUri($resource);
+            if ($uri === false) {
+                throw new ThumbnailServiceException(sprintf(
+                    'Could not generate URI for resource "%s".',
+                    $this->persistenceManager->getIdentifierByObject($resource)
+                ), 1737558490);
+            }
+
+            return $uri;
         }
 
         $staticResource = $thumbnail->getStaticResource();