You can also try deleting the Do you want to have your say when we set our development plans?
Like I mentioned before, I can certainly understand your dissatisfaction with the situation, but I'm in no position to guarantee we won't find any other issues in the future as well.
This particular problem is rather peculiar as we didn't find any differences in the way the style for the column groups and those for other elements are defined, yet only the column groups cause the design-time issue.
Could you please try isolating this and send us more details on the behaviour, so we can troubleshoot it locally. Regards, Petya Telerik Do you want to have your say when we set our development plans?
You can also open a support ticket and attach a sample application where this is reproducible. Do you want to know when a feature you care about is added or when a bug fixed?
Intellisense now fails almost immediately in VS2015.
There are no errors or exceptions thrown and the designer keeps working but Intellisense just stops.Regards, Petya Telerik Do you want to have your say when we set our development plans?Do you want to know when a feature you care about is added or when a bug fixed?There are several resources online where you could find additional information on the topic if you're interested, for example, this MSDN blog post.In short, what you can try is uninstall the official version of the controls from the machine or clean the designer's cache at Please let me know whether that works for you.The other thing worth mentioning is that the source of the problematic behaviour is one of the design assemblies shipped with the Telerik UI for WPF suite.