Reimplement the filter interfaces on the index page that 
allow incremental filtering changes. Just for the currently 
selected filters, not all. 
 

Richard, do you know what this issue means?

1) Is it supposed to have an index page up top and a search page at
the bottom so you can modify the search? (possible limited to just
filter props that are not null??)

2) is it save of the issues in the search and allow another search
just within that list of issues?

3) is it something else?

See the original concept for filtering in https://roundup-tracker.org/docs/images/roundup.png.
It has a series of check boxes that can be used for filter refinement.

It looks like it only exposes fields that are currently being filtered on, so you can choose
different settings but not new fields.

This may be useful:

https://github.com/colinaut/action-table