There are a few features in WordPress we take for granted, like easily being able to insert a ‘Read More’ break in our posts.
But in the new WordPress 5 editor (which was called Gutenberg during its development) finding that isn’t as easy as it should be.
Like all elements in the new editor you need to add it as a block – but you will not find it by searching for a block called read more.
Bizarrely, it’s just called more.
When it actually inserts into the editor it is named read more, which suggests to me this is a an oversight that will hopefully be fixed soon!