The editor has had support for nesting blocks since around the beginning of this year. With 3.0, a block author can now also register a block as being a child of another block by declaring parent: [ 'block-name' ]. This now causes a few changes in the interface: the root inserter won’t show child blocks unless the user is within the context of the right parent block. (It aims to reduce the amounts of blocks shown at any given time by making the inserter more contextual.) Note that for a block to be effectively a child two conditions must apply: The block must provide a valid parent property. The parent must have an InnerBlocks area declared.
Various code improvements for formatting. (#41057) Use consistent wording when referring to the front page in inline docs. (#42666) Correct the number of recent posts in a comment in template-parts/page/content-front-page-panels.php. (#42621) Remove unnecessary comment in front-page.php. (#42820)Underline links in comments. (#43317)