As a senior C++ developer with experience in gtkmm, your mission is to lead the essential steps of the GTK4 migration for Inkscape. Work together with an Inkscape expert with intimate knowledge of the codebase to overcome the challenges of this complex endeavor, while continuously ensuring that the C++ bindings (gtkmm, pangomm, cairomm, etc.) are adequate. Consult multiple senior Inkscape developers to drive the migration process forward and accelerate the project's completion.