REQUEST: Highlighting and Feed Error Resilience

[Cavaldi]

Highlighting
It would be nice if filters had a radio button to choose between blocking items that don't match or highlighting those that do (while letting the rest through normally), and a color button to set the highlight background color.

Feed Error Resilience
A number of feeds which I follow are buggy, which frequently results in re-notification of items.
It would be nice if the content of recent items were cached item by item as checksums and checked item by item against "new" results.
I'd like to request that whatever cache is used to check the newness of items be specifiable by number (per feed). Some feeds update unpredictably yet cause regular re-notifications.