Learn how to test GUI applications directly from CI runners using GhVmCtl, a bash-based tool that leverages LXD containers and KVM virtualization within GitHub runners. Discover how this innovative solution spawns LXD containers inside CI environments to execute various commands, including running snap packages and capturing screenshots in both window and screen modes using gnome-screenshot utility. Explore the practical implementation through real-world examples currently used by Snapcrafters for testing purposes, and understand how this tool enables large development teams to efficiently maintain and test numerous GUI applications with streamlined automation processes.