Board Thread:Support Requests - Getting Technical/@comment-13887979-20180511214154/@comment-168424-20180511215023

Instead of trying to to use the Visual editor, just try adding the following to the end of the URL after you go to the template page: ?action=edit&useeditor=source

You could also try using a different browser. It looks like you're using Chrome, so the VisualEditor should work, but it's possible you have some wiki-wide JS that is interfering with the VisualEditor.