Prerequisites
The step Deploy Solution Package to App Catalog (Latest Server/DC) has been completed.
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If the check mark "Make this solution available to all sites in the organization" was set when deploying the package, it is no longer necessary to add the app per SiteCollection. In that case, the webparts will already be available. Remember to skip the following step!
Instruction
To check that the client-side solution can be added to sites, proceed with the following steps:
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