Transform existing C++ openGL project from glut/freeglut to glfw

Question

I want to upgrade my scientific 3D application from Freeglut to GLFW, but I worried about hidden conflicts or loss of data, Actually my application works like a charm with Freeglut and I don't have any problem, but GLFW is recommended for modern OpenGL(3.0+) in all modern books and tutorials.

I look at GLFW API and It looks like Glut with glfw* prefix, but I'm not exactly sure. so I have three questions in mind:

1. Is it worth to break my existing project for GLFW sake, or stick to freeglut?
2. Am I going to loss any feature from glut?
3. Is GLFW compatible with GTK+? (because my GUI is based on GTK)

Answer 1

3- Is GLFW compatible with GTK+? (because my GUI is based on GTK)

Using GTK+ you should neither use Free-/GLUT nor GLFW. GTK+ has a OpenGL widget and does all the event management. Use that.