Selecting "Activity Order" in forum shows no items
Using the "Activity Order" widget and filtering by selecting a "Forum" causes no items to be displayed.
STEPS TO REPRODUCE - Use the ACTIVITY FILTERS widget to select a forum to which you are subscribed. After getting results, use the ACTIVITY ORDER widget to select what order to display. The result (for me at least) is that no items are displayed/returned.
Looking at the QUERY STRING, I noticed that in the default view, the query variable &pf=1 exists in the string, but is missing after selecting an ACTIVITY ORDER. Manually adding &pf=1 to the query string seems to resolve the issue.
I would have looked and perhaps submitted a PR, but at this point will not be able to do so for some time - even though it seems it should be a relatively simple fix -- so I recorded it here in case someone else gets to it first.