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May we know what version of Configuration Manager you are using, SCCM 2012 or Configuration Manager current branch version 1906? There's no such thing as SCCM 2012 V1906.
It's recommended that you upgrade to the latest Configuration Manager current branch version 2002/2006 and update the latest client agent to get better support for Windows 10 and get rid of Sliverlight.
Based on my knowledge, The application catalog's Silverlight user experience isn't supported as of current branch version 1806. Starting in version 1906, updated clients automatically use the management point for user-available application deployments. You also can't install new application catalog roles. Support ends for the application catalog roles with version 1910.
If you're still using the application catalog website user experience, the client requires Microsoft Silverlight 5.1.41212.0. The client doesn't automatically install Silverlight. The primary functionality of the application catalog is now included in Software Center.
Refer to:Unsupported and removed features
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