What it is
PhotoGIMP replaces GIMP 3's configuration files with a layout that rearranges the toolbox to match Photoshop, applies Photoshop's default Windows keyboard shortcuts, and enlarges the canvas area. It also adds a custom splash screen, icon, and desktop launcher on Linux, with an install script that detects Flatpak or native GIMP and backs up existing settings. People moving from Adobe Photoshop to free software install it to keep their muscle memory while learning GIMP.