Hello, everyone! I've done some research on writing add-ins, and
it looks like it's possible to create customized tool windows.
I'd like to make one that's just like the Output window, and redirect
TRACE strings to that tool window. However, I still want TRACE to
go to Output, so that means I'd have to have a way to write a MYTRACE
"function" to redirect the output to my customized tool window.
Can anyone comment on whether or not this is even possible Thanks!

Customized TRACE + AddIn output window?
FredrikRN
Christophe Lauer
Here is how you can create your own output window:
OutputWindow outputWindow = (OutputWindow)dte.Application.Windows.Item(Constants.vsWindowKindOutput).Object;
outputWindowPane = outputWindow.OutputWindowPanes.Add("Designer output");
after that you can do:
outputWindowPane.OutputString("Your message")