Use the Classic Block to edit content, that was created before the WordPress block editor was introduced, using something similar to the classic WordPress editor.

Screenshot

Example

This is content created in the Classic block.

Notes

• The Classic Block will be used for content generated using the Classic Editor that has not been converted to Blocks.
• You can have multiple Classic Blocks in a post.
• A Classic Block is just HTML that’s not enclosed in block comments. Its block name ( core/freeform ) is implicit.
• If you want to edit content using the Classic Editor – the post editor available before WordPress 5.0 then consider installing and configuring the classic-editor plugin.

WordPress 5.5 updates

The Classic block now has a very obvious “Convert to blocks” action.