Viewing the [[Special:AbuseFilter/history]] page, click the latest revision for any filter. For example, clicking the only entry for "2" in my installation takes me to [[Special:AbuseFilter/history/2/item/4]].
The message displayed at the top of the page is misleading and wrong:
"You are editing an old version of this filter. The statistics quoted are for the most recent version of the filter. If you save your changes, you will overwrite all changes since the revision you are editing."