When user try to load the Visual Editor in Page: pages using ?veaction=edit parameter the loading fails with the error "Error: No class registered by that name: proofread-page".
I happens because the ext.visualEditor.desktopArticleTarget.init code gets executed before ext.proofreadpage.ve.pageTarget.init and, so, the second is not able to load the ProofreadPagePageTarget
It is a follow-up of task T138489