This one worked for me: Generate user API key for Discourse / Robin van Boven | Observable
$ curl -X GET "https://community.openstreetmap.org/groups.json" -H "User-Api-Key: aabababababbabbabbabbabbbabbb832"
{"groups":[{"id":42,"automatic":false,"name":"forums-governance","user_count":4,"mentionable_level":99,"messageable_level":99,"visibility_level":0,"primary_group":true,"title":"Forums governance team","grant_trust_level":4,"flair_url":"landmark","flair_bg_color":"EEE","flair_color":"666","bio_cooked":"<p>People who are helping with this forum governance. <a href=\"https://community.openstreetmap.org/t/which-governance-accountability-model-do-we-want-for-this-tool-who-and-how-should-decisions-being-made/220\">More info and discussion</a></p>","bio_excerpt":"People who are helping with this forum governance. <a href=\"https://community.openstreetmap.org/t/which-governance-accountability-model-do-we-want-for-this-tool-who-and-how-should-decisions-being-made/220\">More info and discussion</a>","public_admission":false,"public_exit":true,"allow_membership_requests":false,"full_name":"Forums governance team","default_notification_level":3,"membership_request_template":"","members_visibility_level":0,"can_see_members":true,"publish_read_state":false},{"id":2,"automatic":true,"name":"moderators","display_name":"Moderatoren","user_count":1,"mentionable_level":0,"messageable_level":99,"visibility_level":1,"primary_group":false,"title":null,"grant_trust_level":null,"flair_url":null,"flair_bg_color":null,"flair_color":null,"bio_cooked":null,"bio_excerpt":null,"public_admission":false,"public_exit":false,"allow_membership_requests":false,"full_name":null,"default_notification_level":2,"membership_request_template":null,"members_visibility_level":0,"can_see_members":true,"publish_read_state":false},{"id":56,"automatic":false,"name":"mods-argentina","user_count":3,"mentionable_level":99,"messageable_level":99,"visibility_level":
...
(User-Api-Key length matches the actual key length)
I have no idea how trustworthy the site is, though…