Known wormholes are now listed on the Empire/Reports section.
As others reports this is only available to Upgraded players.
How it technically works:
- There are listed the wormholes in the regions you have visited/scouted in the last 90 days and was open by then (or a upgraded member of your guild have visited/scouted and you have shared scouted data permission).
- If you have a fleet present at a location with a wormhole you can see all the wormholes (the same if a upgraded guild member has a fleet present and you have shared scouted data permission).