Edge glow effect from 20.12.1c project renders differently in 22.08.1

Tested with kdenlive-20.12.1c-x86_64.appimage, kdenlive-22.08.1-x86_x64.AppImage on Ubuntu 22.04.

To reproduce:

1. Open effects-stylize-20.12.1.kdenlive from erjiang/kdenlive-backcompat
2. Render out the project in both versions listed above
3. See that the second section looks different. In the 20.12.1c version, the edge glow becomes purple. In the 22.08.1 version, the edge glow becomes bright blue and then returns to its original state.