Current version of WebGrid is not designed for compatibility view because it’s IE specific stuff. The tools basically render the pages based on the specified document type. However, the compatibility mode causes the rendering to use old browser mode while the library still consider it as XHTML.

You might want to check another thread that discuss about the similar problem in here. If possible, you can try the approach suggested by Karl Pietsch on thread.

Please let us know whether it helps or not.

Thanks for your response.

I follow your advised and the link fixed the issue. However, it did not fix everything. The issue is now on the other control. The web expander label got shrink after applying the suggested workaround. Please refer to attached screenshot.

The thread in here discusses the same problem happen on WebExpander.
Please kindly let us know whether this helps or not.