Document Library greyed out on Image Gallery web part

OpenBoxChris labrunning 

I too have seen this behavior on my SharePoint site and I think this is a bug in SharePoint code (API call) which retrieves document libraries from current site to bind to the dropdown control.

I noticed below error in developer console of browser when I selected Dynamically display images from a document library option in web part settings:

The expression "Id,Title,RootFolder%2FServerRelativeUrl" is not valid.

& the API call request causing this error is: 

https://<tenant>.sharepoint.com/sites/<siteName>/_api/web/lists?%24select=Id%2CTitle%2CRootFolder%252FServerRelativeUrl&%24filter=BaseTemplate+eq+101&%24orderby=Title+asc&%24expand=RootFolder

But, ideally it should be like: 

https://<tenant>.sharepoint.com/sites/<siteName>/_api/web/lists?$select=Id,Title,RootFolder,ServerRelativeUrl&$filter=BaseTemplate eq 101&$orderby=Title asc&$expand=RootFolder

Hope it will help you & Microsoft to troubleshoot this issue.

CC: VesaJuvonen Mark-Kashman

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