The gov.uk Design System calls this the "Exit a page quickly" pattern [1], with an associated component [2]. It can be activated by clicking the Shift key three times.
There's this nice blog [3] that explains why they chose Shift instead of other keys, and also gives a nice overview of the pattern.
[1] https://design-system.service.gov.uk/patterns/exit-a-page-qu... [2] https://design-system.service.gov.uk/components/exit-this-pa... [3] https://beeps.website/blog/2024-10-09-why-govuk-exit-this-pa...
That blog entry is a delight to read!
> As a result of advertising people being bastards,
The gov.uk Design Team are a treasure.
>It can be activated by clicking the Shift key three times.
Windows Sticky Keys entered the room.
I'm surprised that the blog doesn't mention what, to me, is the most obvious reason not use Esc — because it's conspicuous as all hell! If somebody's at risk and wants to hide what they're doing, their abuser seeing them repeatedly hit Esc just screams "I'm trying to hide something".