How to disable frame (and titlebar) but keep resizing and snap features when using SendMessage to drag the window?

Question

I'm trying to disable the titlebar (and frame), but keep the ability to resize the window and have it so the snap layouts work when triggering SendMessage. I have the trigger work, but when I remove all the bit flags returned from GetWindowLong that gets it to disable the whole frame, none of the native windows features work when I drag my window anymore. So I'm completely lost at the moment on this issue. Does anyone have any solutions they've come up with to disable the frame but keep resizing and/or at least have it so when I drag using SendMessage the snap feature doesn't go away? Also lastly, I do use glfw, but I've been using the function to grab the hwnd and I'm able to add the custom window process using:

SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR)WindowProc);  

Answer 1

The WS_THICKFRAME | WS_MAXIMIZEBOX styles must be set for Snap.

To remove caption + frame, with DWM (https://learn.microsoft.com/en-us/windows/win32/dwm/customframe) or by handling WM_NCCALCSIZE + WM_NCHITTEST