WordPress does not ship a block with that name. My guess is that it was available to you through a theme or plugin you used in the past. Either you changed the theme or deactivated the plugin that provides this block. Therefore, the block cannot be displayed in the editor.
You would have to change the theme back or reactivate the plugin to solve the problem – depending on what applies to you.
Since I couldn’t find any information about this block, I can’t help you with this.
I have migrated from wordpress.com to www.remarpro.com. No plugin has been installed to use such a block on www.remarpro.com. The theme has not been changed either. Simply, in the migration, said block has never appeared, only the banner that I have mentioned.
To whoever reads this thread: How can I fix this?
This reply was modified 1 year, 3 months ago by ncfuentes.
This reply was modified 1 year, 3 months ago by ncfuentes.
So, “a8c” here is a really good clue. It’s an unofficial abbreviation of “Automattic”, the company behind WordPress.com, Jetpack, WooCommerce and a bunch of other useful things.
So it looks like .com uses their own in-house plugin that enables a few useful things, but this plugin may not be readily available for self-hosted sites.
You may look for more details about the “Query” block. It may have some of the functionality you need.