I have a project which is written using visual C++. I have successfully ported a tabbed dialog box to use Code::Blocks wxSmith with wxWidgets on Windows 10. However the whole purpose of the exercise is to see if I can move the application to Ubuntu Linux. I have managed to install Code::Blocks 16.01 to Ubuntu 16.04 and transferred the project and got it to compile and run. My problem is that the properties are different between the two versions of Code::Blocks. I am using a FrameWindow that has a wxNotebook with pages of wxBitmapButtons controlled by a wxGridBagSizer. This arrangement worked on the Windows 10 system but the Identical wxSmith XML produces a very different effect on Linux. I need the entire face of the button to be the bitmap that is loaded into the button and the button faces to be touching each other. The wxBitmapButton while doing exactly this on Windows 10, is instead, on Linux, surrounding the bitmap with something like 15 pixels of white space and enlarging the button in the process so that the buttons do not fit into the window space provided and look spaced out and silly. To summarise, wxBitmapButton appears to be a full bitmap button on Windows but only half a bitmap button on Linux. Is there a solution to this problem? I am using version 3.0 of wxWidgets.