In Fiddler you can:
These filters do not show up in the Filters tab. Mine is empty:
How do you see the list of filters you've added? How a filter you've added?
Once you've added filters, they show up below the list of sessions:
Each filter looks like a link. It is underlined when you mouse over it. But clicking on it does nothing which is a bit confusing.
Right clicking on a filter removes it. This means that future traffic will not be filtered. However, removing a filter does not restore "hidden" sessions to the list. Filtered sessions seem to be removed.
The number in parenthesis, Filters (8), is the count of how many sessions have been hidden.
Closing and restarting Fiddler also clears that list of filters.