diff --git a/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js b/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js
index 4691fa859..9c87d2244 100644
--- a/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js
+++ b/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js
@@ -52,6 +52,9 @@ function initTagField(id, autocompleteUrl) {
  *    - alwaysDirty - When set to true the form will always be considered dirty,
  *      prompting the user even when nothing has been changed.
 */
+
+var canDirtyFormCheck = true;
+
 function enableDirtyFormCheck(formSelector, options) {
     var $form = $(formSelector);
     var $ignoredButtons = $form.find(
@@ -72,7 +75,11 @@ function enableDirtyFormCheck(formSelector, options) {
             }
         });
 
-        if (!triggeredByIgnoredButton && (alwaysDirty || $form.serialize() != initialData)) {
+        if (!canDirtyFormCheck) {
+            triggeredByIgnoredButton = true;
+        }
+
+        if (canDirtyFormCheck && !triggeredByIgnoredButton && (alwaysDirty || $form.serialize() != initialData)) {
             event.returnValue = confirmationMessage;
             return confirmationMessage;
         }
diff --git a/wagtail/wagtailadmin/static_src/wagtailadmin/js/page-editor.js b/wagtail/wagtailadmin/static_src/wagtailadmin/js/page-editor.js
index 5ee29529b..79508d364 100644
--- a/wagtail/wagtailadmin/static_src/wagtailadmin/js/page-editor.js
+++ b/wagtail/wagtailadmin/static_src/wagtailadmin/js/page-editor.js
@@ -366,11 +366,13 @@ function initCollapsibleBlocks() {
 
 function initKeyboardShortcuts() {
     Mousetrap.bind(['mod+p'], function(e) {
+        canDirtyFormCheck = false;
         $('.action-preview').trigger('click');
         return false;
     });
 
     Mousetrap.bind(['mod+s'], function(e) {
+        canDirtyFormCheck = false;
         $('.action-save').trigger('click');
         return false;
     });