Office Add-In Shared Runtime Error Invalid child element 'Runtimes'

Question

I am trying to implement the JavaScript Shared Runtime for an Office.js Excel Add-in, but when I add the <Runtimes> element I get the following error:

The element 'Host' in namespace 'http://schemas.microsoft.com/office/taskpaneappversionoverrides' has invalid child element 'Runtimes' in namespace 'http://schemas.microsoft.com/office/taskpaneappversionoverrides'. List of possible elements expected: 'AllFormFactors, DesktopFormFactor' in namespace 'http://schemas.microsoft.com/office/taskpaneappversionoverrides'.

Answer 1

I fixed that by adding Runtimes to the local xsd file. In my machine it is located at:
C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Xml\Schemas\1033\TaskPaneAppVersionOverridesV1_0.xsd

Go to the corresponding schema and search for Runtimes, then add these parts to the local xsd file.
https://learn.microsoft.com/en-us/openspecs/office_file_formats/ms-owemxml/82e93ec5-de22-42a8-86e3-353c8336aa40

Note that this hasn't been tested with the add-in published to the Microsoft Store.