Charts: Standardize Color for Blank values (RE: Sync Colors)

Right now, when the "sync color" button is selected in chart settings to apply tag colors to a chart automatically, blank values are assigned a random color. At best, this makes charts displeasing to the eye and mis-matched across a dashboard. At worst, it leads to misreading the data (i.e. the random color assigned to blanks is the same as an existing value). See screenshot for an example of this behavior.

While one can manually set the color for blank values, this only helps as long as the data remains stable (as long as blanks exist). If, by chance, there are no blank values for a period of time and then a blank reappears, the color for blank values would again be randomly assigned -- with no notice to the chart owner.

Adding a standardized color for blanks (either automatically across all aha accounts, or manually customizable just as other field values) would close the gap in the "sync colors" function, ensuring all values in a field have standardized colors for consistently clear and legible reports.