Category filter doesn’t work on “User visits” graph
Steps to reproduce:
- Head to your admin dashboard, then click on “User visits” to bring up the graph.
- Change the category from the drop-down and click “Refresh report”.
- Note that none of the values have changed.
According to this graph, every single user was able to visit a category months before I created it. 
Expected behaviour: The graph should show statistics only from the selected category.
Date range doesn’t revert when cleared out
Steps to reproduce:
- Head to your admin dashboard, then click on “User visits” to bring up the graph.
- Take note of the default date range.
- Change the date range and click “Refresh report”. (You can widen or narrow the range.)
- Delete out the dates in the range and click “Refresh report”. Note that you’re still seeing the date range from
, not from 
. - You can even refresh the page and the range won’t revert to default.
Expected behaviour: Clearing the date range out should revert to the default date range.
Date range gets confused when only field populated
- Head to your admin dashboard, then click on “User visits” to bring up the graph.
- Change the “until” date to some time in the distant past and click “Refresh report”.
- Note that the graph draws the axis and legend, but no details; there’s no error message.
Expected behaviour: Ideally, it shouldn’t be possible to run the report with only one date range; setting one should set the other if it is blank to some sensible default (a month/week in the past/future, as appropriate?) Alternatively, a message should be shown.
Inappropriate filters shown for some graphs.
I can filter by category for:
- New users
- User profile views
- Emails sent
On none of these does changing this filter actually do anything – nor should it, as it’s meaningless. This filter shouldn’t be shown on those charts.
Aside: I collected all of these up into one topic as they seem to be closely related. Is it preferable to instead post each of these as a new topic?
