Memory usage is displaying differently

Hi I noticed ever since the update of MainStage, that the memory meter looks different. It now has two indicator bars. One is showing 1/4 and the other is almost half and seen in the picture. I’m not sure what the lighter grey bar is indicating. I’m afraid that MainStage is limiting the amount of ram used. I have 16 of ram so I want use everything needed.

The reason this came up because we are getting more and more sticky keys, and overload messages. This should not be happening considering the specs of the mac

Thanks.