List context menus offer actions for the selected field or record. Show Matching can build a condition from a value you are looking at. Filter Out excludes that value. Check the resulting breadcrumb because a convenient menu action can replace or combine with a condition you already had.
A saved filter stores a reusable definition, not a frozen copy of the current rows. New matching records should appear the next time you run it. Give the filter a name that describes its purpose. Inline editing changes a record directly from the list when the field and permissions allow it. It is still a data change, so verify the record number before committing an edit. A read-only number stays read only regardless of the editing surface.