Hi @Hans Hallebeek
Do you want to use JavaScript technology to build Office add-ins?
According to the article 'Office Add-ins platform overview', and 'Access and explore Office add-ins in Word, Excel, and PowerPoint for the web and Windows', JavaScript can build custom web Office add-ins that are different from COM and VSTO add-ins, the web Office add-ins can be used on Microsoft 365 Apps, and deployed and published to users within the organization, but currently not available on non-Microsoft 365 apps.
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