Color Replacer

works like aseprite shift+r but you can use it even when dialog box is open to pick colors with eyedropper tool changing your chosen color to background color.  Works on frames.

works with rgb and indexed color mode.

Installation

1. Open Aseprite
2. Go to File → Scripts → Open Scripts Folder
3. Place downloaded LUA files into previously opened directory
4. Restart Aseprite
5. Add a keyboard shortcut

You will find installed scripts under File → Scripts menu.