Automatically share WordPress posts on Mastodon.
Supports image uploads (and alt text), custom formatting, and so on.
Share on Mastodon is compatible with the classic as well as the block editor ("Gutenberg").
Share on Mastodon supports 3rd-party apps, too, on the condition that the "Share Always" setting is enabled. (And, for more fine-grained control, there's a filter hook.)
Share on Mastodon can also be added as a Micropub syndication target, allowing you to enable (or disable) sharing right from your Micropub client. (You'll want to disable "Share Always" for this.)
Complete documentation, and code examples, can be found at https://jan.boddez.net/wordpress/share-on-mastodon.