How to remove an overlay from the list?

To remove a custom overlay from the list, open the bottom menu (either with a right-click or with a swipe from the bottom) and go to Overlays > "Add KML/GPX/GeoJSON files".
Pick the overlay you want to remove and some options will appear at the bottom. You will be able to either remove the overlay from the map (hide it) or remove it completly from the list.

Note that default Maps Pro overlays (Google Traffic, etc.) cannot be removed.

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