Problems installing plugins in Image J

I am running macOS Catalina 10.15.5 and I downloaded the SplineSnake plugin, however it does not appear when i search for it in Fiji, even though I can see when I look to see where the plugin is located manually that it appears in the plugins folder.

Would anyone be able to help explain why it is not appearing, I have tried the methods in other posts but they don’t seem to have worked