Replace all references to [MM_URL] with the MM site reference. E.g. if MM is installed at mm.digizuite.com, then replace [MM_URL] with mm.digizuite.com. (Make sure to append /oc add the end of the mm site reference)
Change the ID to a new, random GUID.
Change the "DisplayName" (title) and the "Description" appropriately. The "DisplayName" is the title in the top of the add-in pane (red line below),
Change each “bt:Image" element if the user wants to use a different icon than the default provided (Make sure to append the image extension to the MM site reference e.g. https://mm.digizuite.com/icon.png)
Go through the labels in the manifest file and ensure that they have the desired values. In particular, the "residOpenButtenText" is the displayed title for the ribbon (blue line below).

Manifest validation

To validate the changes to your Office Add-in manifest file, you can install the office-addin-manifest npm package. This tool allows you to check your manifest for any issues. For detailed instructions on installing and using the package, refer to the official Microsoft guide: https://learn.microsoft.com/en-us/office/dev/add-ins/testing/troubleshoot-manifest#validate-your-manifest-with-office-addin-manifest .

Manifest deployment

To deploy the manifest and thus make the OC available for users, go through the following steps with an Office 365 admin account: https://docs.microsoft.com/en-us/microsoft-365/admin/manage/manage-deployment-of-add-ins?view=o365-worldwide

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