When I add a block to a page to show the latest posts for a category, the “Read more” option shows up (if a manual excerpt is not on the Post and reading settings are correct), but it doesn’t go to the full post page.
This behaves differently than a regular blog archive list page. I see about adding a “more” element inside the post itself, but that does not help in the Latest Posts Block (using Gutenberg block editor).
I can show examples on a live site, but I’ve disabled a “read more” link since it doesn’t work.
Can I see the read more link you’ve added? Perhaps the link specified on the link you’ve manually created doesn’t point to the correct link.
Also, you seem to be making the Latest post manually but is it dynamic? If isn’t and you wish to make it always display the actual latest posts consider using a plugin.
If I may suggest, consider using WP Show Posts to show the Latest Posts on your sidebar rather than making your own custom block. It actually has its own Read more button built in so you’re sure the Read More button works.
A wise man once said:
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