Thanks for the feedback indeed!
We actually made the grouping to ease the control discovery, but it seems not to work for everyone. Well, an option we are considering is that we provide the choice of having the Toolbox items grouped or not grouped during installation and/or Toolbox configuration (VSExtensions).
How's your opinion about that?
P.S. In the meantime, you could start typing a control name having the Toolbox active (e.g. hovered with the mouse) to navigate to the item quicker. I know this is not the best workaround, but it might still help.
the Telerik team
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