I’ve added the ability to conveniently open corresponding files. For example, having stdafx.h opened you can now quickly open stdafx.cpp and vice versa. It works for all combinable extensions that Tabs Studio supports.
Open corresponding file command was added to the top of the tab’s context menu:

Open corresponding file command in context menu
There could be multiple corresponding files to select from:

Multiple corresponding files
TabsStudio.Connect.OpenCorrespondingFile Visual Studio command was also added to be available for keyboard binding. This command looks for all available corresponding files relevant to the currently selected tab and opens first one from the list. If all corresponding files are already opened, OpenCorrespondingFile activates next extension as NextTabExtension command does. Having standard h/cpp pair this behavior allows you to hit OpenCorrespondingFile shortcut and get to a corresponding file no matter if it is currently opened or not.