Or have I read this wrong?
www.bbc.co.uk/news/entertainment-arts-22028738
"The British Library and four other "legal deposit libraries'" have the right to collect and store everything that is published online in the UK.
...
The archive will cover 4.8 million websites and will include magazines, books and academic journals as well as alternative sources of literature, news and comment such as Mumsnet, the Beano online, Stephen Hawking's website, and the unofficial armed forces' bulletin board, ARRSE."