Alpha in Map Hover not working as expected

[StephanieM]

Hi all:

 

I'm trying to get the effect of a brightening of an area in FusionMaps when I hover over it. The underlying colour from the data should remain. For example, a state with no data is a light grey, one with a value of, say 5 is green and progressing up to red for higher values. I would expect the following two parameters:

               entityFillhoverColor:"#FFFF88",
                entityFillhoverAlpha:"40",
to apply a transparent yellow tint to whatever colour is already there, making it simply appear brighter. That is, the grey should lighten up and go yellowish, the green should appear a brighter yellow-green and a red should be a nice orange.

 

What I get is a flat, very light yellow regardless of the underlying colour.

 

Am I missing something? Can I actually do this? Is this a browser limitation? Or (gasp) a bug?

 

Mac OS X 10.7.5 (yes, ancient but that's as high as I can go)

Firefox 43.0.2.