A special level of accessibility failure on Egencia‘s mailing list subscription management page: the labels for choosing which individual mailing lists to subscribe to are properly-configured, but the “unsubscribe all” one isn’t. Click the words “unsubscribe all” and… nothing happens.
But it gets better: try keyboard-navigating through the form, and it’s hard not to unsubscribe from everything, even if you didn’t want to! As soon as the “unsubscribe all” checkbox gets focus, you get instantly unsubscribed: no interaction necessary.
My first instinct was to call this a dark pattern but through your keyboard navigation test and it triggering the action from focus alone, I suspect this is just a sloppy Javascript implementation.
The event the script is listening to isn’t likely specific enough and was never properly tested.