check if Gutenberg is currently in use

You'll need WP_Screen::is_block_editor() method to check if you are currently in the Gutenberg Editor (Since WordPress 5.0). Also, if you install Gutenberg as a separate plugin, then you'll have the is_gutenberg_page() function available to do the same check.

1. How do I check Gutenberg usage?
2. How do I use Gutenberg in WordPress?
3. What is Gutenberg website?

How do I check Gutenberg usage?

How to detect the usage of Gutenberg

1. gutenberg_post_has_blocks() - this function exists only in Gutenberg plugin, and not in 5.0 Core.
2. is_gutenberg_page() - the same.
3. the_gutenberg_project() - the same.
4. has_blocks() - does not work (returns false) when Classic Editor is on and its option "Default editor for all users" = "Block Editor"

How do I use Gutenberg in WordPress?

New Gutenberg editor comes with a default Table block, which makes it super easy to add tables into your posts and pages. Simply add the block and then select the number of columns and rows you want to insert. You can now go ahead and start adding data to table rows. You can always add more rows and columns if needed.

What is Gutenberg website?

In a nutshell, Gutenberg is a brand new editor for the WordPress platform. It will radically change the way you create posts, pages, products, and just about everything else on your site. Gutenberg will arrive as part of WordPress 5.0, which could be released as early as November 27, 2018.