Move the cursor around using arrow keys and place a pixel using Enter or Space. You can adjust the color/saturation using the sliders. It is recommended that you use this on Turbowarp with infinite clones enabled.
If there is an X before it that means it was patched. Known issues : X Significant performance issues when an image is loaded. The cursor misaligns when you move it into the menu. X Hues/saturation/brightness don't properly load into the editor sometimes.