Colors of the MOPPI icon
The MOPPI icon can have two colors:

When the icon is blue, Optimizely runs on the page. A number in the lower right corner additionally shows the number of running experiments. Remember that it may take a second or two for the icon to update its color. This also depends on the way you have included Optimizely ( synchronous or asynchronous ). In order for MOPPI to work, Optimizely must first be executed.

But if the icon is grey, Optimizely does not run on the page and MOPPI cannot display detailed information.