With the new update giving an option to add a slicer as a dropdown, I found that the scrolling up or down on the slicer does not work on Dashboards or embedded reports.
It works on PBI Desktop
I cannot repro the issue here. Please refer to following gif, the scroll is working well in dashboard.
This is only on the embedded dashboard to SharePoint page.
If you click the scroll bar and drag it down, can the scroll bar moved down? BTW, there are some fixes for the dropdown mode slicer in next month release, you can wait for the next release to see if this issue persists.
I have the same problem, but only in Internet Explorer 11. Instead of scrolling in the slicer it will scroll the whole page, even if you click the scrollbar. Even after selecting something in the scrollbar the slicer will not move when scrolling.
It works fine in chrome!
I got the same problem for the hierarchy slicer, Power BI Desktop. Slicer is scrolled down to 6 top values, and does not go down any further.