It is never simple

I had occasion to delve into drag and drop and I could write a book about that as well as program it in 5 languages through 4 interfaces. The core is a shared data structure, and you wouldn't think that would be all that hard to handle, but when you pour in a cup each of Wayland, cross platform compatibility, Qt, GTK, wxPython, C++, C, X11, Windows, Mac, and a lack of strong common purpose, you get a bitter tasting soup.( While studying Schmidtea mediterranea and monitoring courses in embryology and proteomics as well as distributed AI visual hash analysis in a UDP network.) It isn't any fun unless it is impossible.
In the process I went through Mozilla source, Qt sources, GTK, X11 specifications and created several programs in python, C and C++. Now I know that GTK arises from GIMP toolkit and Qt is Trolltech and they are different animals altogether. The reason I even dived into this seemingly bottomless pit of complexity, is because I couldn't drag and drop from Firefox to wxPython, and every other application including chrome was inter-operable. That seems a bit odd considering the origins and intent as you would think that Firefox would want to be perfect on a major Linux distro. So I jumped and 20 hours later I hit the bottom unexpectedly. Now I know and I can code it directly in X11 C code, which is what I like to do just for fun and on top of that I can solve the incompatibility with some automagic. I am not sure what I have gained, except that it lets me know that I can dive from the UI to the deepest levels of machine code and not lose my way.
That is nothing, when you start to look into things like javascript in PDF, phone cloning, XSS, and the complexity of billions of people on the same phone line with far less than common purpose, more like conflicted and bounded chaos, it becomes so complex and mutable that Alice would consider the predictability and normalcy of Wonderland a welcome retreat.

XEvent.xclient.data.l[0] = automagic(GLint sleep, (char *)("perchance to dream"));
__asm__
nop ; = 90h or 0x90 if you are so inclined
sti ; Yes I am only sleeping to be awakened rudely
0xF4 ;HLT is a privileged instruction; #GP(0) if the current privilege level is not 0 
; 5 clock cycles from nirvana.....

Or maybe I can go deeper down to the transistor.

Or to the electron and then the quark and then ride a neutrino through a black hole.

 All in a day's work.