I am having trouble with the new colour by dimension feature when trying to use a variable to define the colouring dimension.
It seems that any attempt to use an expression to determine the dimension by which colouring should occur results all bars being coloured grey. I have tried defining a measure in the master items but I can only ever get the 'null values' colour to be selected.
Screenshots that explain the issue are attached below.
Using colour by expression could be an alternative, but losing the legend makes the chart difficult to read.