Sure I’ve been building WordPress sites since 2008 but today I found out about the
spinner class in the WordPress admin, mostly because I figured that WordPress had something to do AJAX related spinners so a user had some idea that stuff was happening.
That’s all it takes to get a spinner in the WordPress admin. Add
is-active to show it. Back in 2015 Helen wrote more about them.
Still learning lots of new stuff about WordPress after all these years.