Release capacity bar: show hover over amount for the unused remaining capacity

When using capacity planning for individuals, the bar below the release shows the:

i) work done, ii) work remaining, iii) work remaining over capacity, and iv) any unused capacity in gray if applicable.

When hovering over the portions of the bar, the first 3 above display the amounts. However, when hovering over the remaining unused portion in gray, there's no hover over data.

It would be helpful to have the gray portion show the unused remaining capacity when hovering.