Hi Per Holmqvist,
Thank you for contacting us.
Unfortunately I do not think I understand completely your scenario. I was going to suggest to use RadTabStrip to achieve your case, but it does not offer splitting functionality. And, as you have noticed, we do not offer a separate splitter control yet. The other control I was going to suggest is RadDock - especially Tabbed document example. However, you say that RadDock does not offer all the features for your needs. Do we have an online ASP.NET example
of what you are after? It will help us grasp your needs and hopefully provide you with a better reply.
the Telerik team
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