To me it still seems fairly clear which tab is being focused since it's the only one outlined. I think separating the tab into its own bubble may pave the way

To me it still seems fairly clear which tab is being focused since it's the only one outlined. I think separating the tab into its own bubble may pave the way for more interesting UI in the future. These bubbles could be stacked or displayed vertically while remaining aesthetically consistent. These tabs also seem to more clearly communicate that they can be dragged around.