Placing an environment variable into a user-command/Application "Path", causes QTTabBar to crash every time you try and go back into the QTTabBar options. The only way to resolve the issue was to delete the user-command/Application from the registry.
As a side note, QTTabBar Arguments %f% etc, cannot be used in a command prompt.
E.G.
Path: cmd.exe
Arguments: /k ECHO %f%
Results in a command prompt that displays "ECHO OFF"
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Placing an environment variable into a user-command/Application "Path", causes QTTabBar to crash every time you try and go back into the QTTabBar options. The only way to resolve the issue was to delete the user-command/Application from the registry.
As a side note, QTTabBar Arguments %f% etc, cannot be used in a command prompt.
E.G.
Path: cmd.exe
Arguments: /k ECHO %f%
Results in a command prompt that displays "ECHO OFF"