diff --git a/packages/edit-site/src/components/editor-canvas-container/style.scss b/packages/edit-site/src/components/editor-canvas-container/style.scss
index 52ac29da0696f..07d666fb293c5 100644
--- a/packages/edit-site/src/components/editor-canvas-container/style.scss
+++ b/packages/edit-site/src/components/editor-canvas-container/style.scss
@@ -1,6 +1,10 @@
 .edit-site-editor-canvas-container {
 	height: 100%;
 
+	// This is the gray background color that's applied behind "isolation mode".
+	// The color normally comes from .editor-visual-editor, but that class is missing here.
+	background-color: $gray-300;
+
 	// Controls height of editor and editor canvas container (style book, global styles revisions previews etc.)
 	iframe {
 		display: block;