Hi @infraops, thanks for your post! After migrating to Confluence Cloud your inserted Lucidchart diagrams will need to be converted before they will display properly. You can do this by navigating to the Lucidchart app configuration section, selecting the "Confluence Conversion" tab, clicking the "search" button to locate existing Lucidchart macros, then you can convert the results.

Please note that Confluence treats the Lucidchart add-on as a user. This means for the add-on to access and successfully convert existing Lucidchart macros it must have the correct permissions. If you experience trouble going through the conversion process please check the space permissions to make sure any space or page that wholesale fails to convert is opened to the "Lucidchart Diagrams Connector" user.

Please also note that in order for this to work, your account still needs to be connected to the Lucidchart Connector in your Confluence Server instance!

You can also find this information in our Migrate Lucid documents in Confluence Help Center article.

For information on how to convert your Gliffy diagrams, please take a look at the Convert Gliffy to Lucidchart in Confluence article. 

Please let me know if you have any further questions!