Feature request: Save filter in Test Run

When I create test run with specific configuration and select test cases I want to use filter (filter cases by milestone, platform). It works just fine.
But when I later added new test cases for the same milestone and platform I want to refresh test run. When I open it again my filter is reset - so I need filter cases from the scratch and need to remember what filter I used last time.
This is quite inconvenient - would be nice to have filter stored inside test run/configuration