List all registered WordPress Gutenberg Blocks. Paste this snippet in Chrome Dev Tools Console while in the Gutenberg editor view.

list-all-registered-gutenberg-blocks.js

let types = wp.blocks.getBlockTypes();

// filter to just the core blocks
let core_blocks = types.filter(
 type => type.name.startsWith('core/')
);

// grab just the names
let block_names = types.map(type => type.name);

// display in the console
console.log(block_names);