Hello Ola Karlsson,
The behavior you are describing is not intentional and we do not seem to be able to reproduce the problem on our side. Can you verify that there is an ".extmap.xml" file for every assembly in the folder with the DLLs you have referenced in the project? (They might have been deleted accidentally.)
If the problem persists, do not hesitate to contact us again.
the Telerik team
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