Field Parameters not working in some visual types when another field is added to Category

Up until a couple weeks ago, I was able to use the Treemap visual in a report on the service that uses a Field parameter to allow users to select the granularity that the data is shown and drill up/down between levels. However, there now seems to have been a change which no longer allows this to work when there are multiple fields in Category.

Specifically, when two or more fields are selected in the Field Parameter slicer and there is another field other than the Field Parameter in Category, the Treemap only shows the field below the Field Parameter. Also, the visual header does not display the option to drill up/down between levels. Below is an example of this where the field parameter slicer has Workspace State and Workspace Type selected and these are shown in the Matrix, but not the Treemap. The Treemap only displays the data at Workspace Name level. 

The other visual types that also have the incorrect behaviour occurring are Pie charts, Doughnut charts and Scatter Plots.

The obvious solution would be to remove the second field (Workspace Name), however this is required for DAX calculations so the field must be kept.

This issue is only seen on the service. In Power BI Desktop, the visual is displayed correctly.

Is anyone else experiencing this issue or can anyone replicate this behaviour?