Hello,
The RadEditor
InsertExternalVideo dialog uses iframe to show the video.
In SharePoint usage of iframe elements is not recommenced and especially using it in an editable web part page could be restricted due to security reasons.
The iframe elemnts are not stripped from the RadEditor controls. You can
this thread for additional information.
In
this Stackoverflow thread is discussed the video sharing matter under SharePoint where some suggestions are provided. As an alternative, you can
implement a custom tool that adds a proper video that is supported in SharePoint.
Regards,
Ianko
Telerik
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