to be echoed at the top of the edit form as wikitext. Return true without altering
$error to allow the edit to proceed.
+'EditPageBeforeEditButtons': allows modifying the edit buttons below the textarea in the edit form
+&$buttons: Array of edit buttons "Save", "Preview", "Live", and "Diff"
+
'EditSectionLink': Override the return value of Linker::editSectionLink()
$skin: Skin rendering the UI
$title: Title being linked to