Regression on subsequent searches with r5744

I've set the search filter to search all messages and all works fine when I use it to search for a specific string the first time.

But after discarding the filter detail via the [-] button (next to "Details" and "Save) two different regressions are noticeable

1. The search field still contains the previous search string although the message list isn't filtered anymore.

2. If I use the previous search string again, it only makes the message list the first responder but doesn't filter again.

I have to filter using another search string and then revert to the previously used search string to see an effect.