Caused by: java.lang.NullPointerException: null
08.08.2019 22:28:02.302 *ERROR* [10.250.9.210  GET /mnt/overlay/dam/gui/content/assets/metadataeditor.external.html HTTP/1.1] org.apache.sling.engine.impl.SlingRequestProcessorImpl service: Uncaught SlingException
Tags were migrated from etc/tags to /content/cq:tags as adobe recommended.
Can you share a few more lines of the stack trace? It will help in understanding where is the nullpointer observed.
Also make sure to restart the Day Communique 5 Tagging OSGi per instructions for tag migration.
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