• go to https://en.wikipedia.org/wiki/Special:Log
• in the first combo box, select a log that has multiple action types, such as the Page Curation Log (an "action" is a filter or a subtype for certain logs, whether the log has this feature and how many it has is dependent on the specific log type)
• click "Show"
• the page will reload, and now there will be a useful "action" combo box at the bottom that allows you to filter the entries in just that log

I propose that we use JavaScript to add/update/remove the action combo box when changing logs, without needing to submit the page. Folks may not be able to easily find the action filters otherwise.