is there such a thing as 'british humour'?

A black sense of humour:

List of expressions related to death - Wikipedia

Monty Python and the Holy Grail: Bring Out Your Dead - YouTube

Monty Python: The Dead Parrot - YouTube

Looking at politeness:

"I can't eat this: these prawns are disgusting!"

Or: "I think these prawns might be a bit off..."

The Prawns Are Off | Fawlty Towers | BBC Comedy Greats - YouTube

The British are very good at making comedy programmes:

Jay Doubleyou: what 'the office' can teach you about how to do business

Jay Doubleyou: political satire on film

All My Friends Hate Me (Official UK Trailer) - in cinemas 10 June | BFI - YouTube

All My Friends Hate Me Clip - in cinemas 10 June 2022 | BFI - YouTube

British institutions can make fun of themselves:

Jay Doubleyou: the royals have a sense of humour

Jay Doubleyou: british humour

And:

Jay Doubleyou: shakespeare

Jay Doubleyou: to be or not to be: the intonation is the question

Shakespeare Live! From the RSC on Vimeo

Jay Doubleyou: to be or not to be: to write a book about shakespeare... or not

But maybe there's no such thing:

Jay Doubleyou: there is no such thing as 'national humour'

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