Never you say? https://en.wikipedia.org/wiki/Doggerland

*stares at continental shelf depth map around the UK described on old European map on wall

Ha yes well... "the continent" refers to the European land mass. C.f. "continental breakfast". But the UK is part of the European continent in the continental shelf sense. The word "continent" is not really well defined. Here's a nice video about it:

https://www.youtube.com/watch?v=hrsxRJdwfM0

It does seem poorly defined. If it were the land mass, I would expect that Europe extended all the way to the other end of Russia.