Current ‘main’ branch (e10e8d…) has an empty mura.min.js file in

admin/assets/js

.This file is loaded in

core/vendor/ckeditor/plugins/murafilebrowser/filebrowser.cfm

when adding an image to a content page and clicking on ‘Browse Server’ in the Image Properties pop up. Switching this to use the non minified version then errors on

$("#spinner")

in filebrowser.js as jQuery not loading.