[SDL1] MacOS Mojave blank screen problem

(I have to use an old library and that is why I must use SDL 1.2)
I am using the SDL and SDL_ttf frameworks and C++. When I run the compiled program in Mojave, it only displays a grey window. The title and the dimensions of the window are the only two visible things I can change. The compiled program runs on El Capitan and High Sierra without issues, but on Mojave it only displays a grey window.
It uses the SDL Video mode with double buffers ( no OpenGL).

Is there any way to solve this issue/bug?