Quick links: documentation · itch.io page
Versions: GameMaker: Studio, GameMaker Studio 2
Platforms: Windows, Windows (YYC)
Important
Virtually every use of this extension is superseded by Gameframe, and in a non-fragile way - see Things To Be Aware Of.
This fancy extension addresses a quirk where GameMaker games cease to update while the window is being dragged around or resized.
The issue is Windows-specific behaviour - unless you run game logic and rendering on separate threads, system's dragging/resizing logic overtakes anything else and no other code executes until that's done.
The approach this extension takes is best called "a delightful hack" - the DLL starts up an simple helper program, into the window of which the game's window is then inserted as a child window.
This has the game window continue to run while the window is being manipulated, as well as allowing to enable/disable the window frame, allowing to also use it for borderless fullscreen.
The extension also includes its own versions of Window Commands functions.
Note: Don't forget to disable the default border in Global Game Settings - Windows - Graphics (GMS1) / Game Options - Windows - Graphics (GMS1) / Game Options - Windows - Graphics (GMS2)!