When you click on the custom tab it opens a dialog with the text:


To reproduce.
Add a project to a workspace.
Add another project to the workspace.
go to the properties for the inactive project and click on the custom tab.

Clicking on the includes tab doesn't prompt you for anything it just stays blank.

Here is a screen shot.

This is not a bug but rather an expected behaviour. "Includes" tab can't be opened for an inactive project and that dialog asks if you want to activate it.

I was clicking on the custom tab not the include tab.

then it's a bug indeed and will be fixed in build 5021