Why am I seeing "No filters available"?
You'll usually see the "No filters available" message if your Event field is still set to "All Events".
If you change this to a specific event, you'll see additional options if they are available for your account, and you'll be able to use the "Filter by" field as expected.
How do I add more filters?
Currently, the "Filter by" field allows one selection for event filters.
If you need additional filtering, we suggest creating a Custom Event in your Mixpanel account, including any required filters. Then, you can display the Custom Event in Geckoboard.