Dynamic hierarchy using fields parameter works on desktop but not on cloud service

We too are noticing an issue on our side exactly the same.  Users are not happy.  Behavior seems to have changed within the past week or so, in the Power BI service (Fabric) itself.

Steps to reproduce:
1. Create a field parameter

2. Assign hierarchy related fields from one dim in order.

3. Assign hierarchy related fields from another dim with fewer fields in order.

4. Create a calculated column to group the fields into groups relative to their hierarchy.

5. Place the field parameter on the ROWS well of a matrix, and place some measure on the matrix to roll up.

6. Create a hierarchy slicer based on the field parameter with the group column first, then the field parameter column as second.  Make the slicer multi-select.

7.  Select the first grouping with more columns.  The matrix rolls up to the top level.

8. De-select the first grouping with more columns and select the second grouping with fewer columns.  The matrix rolls up to the top level.

9. De-select the second grouping and select the first, the matrix correctly rolls back up to the top level.

10. Publish the report to Fabric workspace and repeat steps 7-9.  In the Fabric service online, the drill-level for the matrix will not correctly re-set when transitioning back from group2 to group1 - it always shows the lowest level of whatever was selected with Group 2.

Really annoying.