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Provide cloud site URL
Enable log on server side https://confluence.atlassian.com/doc/configuring-logging-181535215.html#ConfiguringLogging-TemporarilychangeloggingbehaviourwhileConfluenceisrunning
com.atlassian.migration
com.atlassian.plugins.confluence.markdown.confluence-markdown-macro
Update CCMA and Markdown Macro server app to latest version (for more accurate error message)
Trigger a new migration and report back to us with the screenshot of CCMA UI (with the message section expanded) and server app logs.
Analyze progress report message
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