--- a/devtools/client/inspector/layout/components/GridList.js
+++ b/devtools/client/inspector/layout/components/GridList.js
@@ -36,17 +36,17 @@ module.exports = createClass({
     } = this.props;
 
     return dom.div(
       {
         className: "grid-container",
       },
       dom.span(
         {},
-        getStr("layout.overlayMultipleGrids")
+        getStr("layout.overlayGrid")
       ),
       dom.ul(
         {},
         grids.map(grid => {
           let { nodeFront } = grid;
           let { displayName, attributes } = nodeFront;
 
           let gridName = displayName;

--- a/devtools/client/locales/en-US/layout.properties
+++ b/devtools/client/locales/en-US/layout.properties
@@ -24,8 +24,12 @@ layout.gridDisplaySettings=Grid Display 
 
 # LOCALIZATION NOTE (layout.noGrids): In the case where there are no CSS grid
 # containers to display.
 layout.noGrids=No grids
 
 # LOCALIZATION NOTE (layout.overlayMultipleGrids): The header for the list of grid
 # container elements that can be highlighted in the CSS Grid pane.
 layout.overlayMultipleGrids=Overlay Multiple Grids
+
+# LOCALIZATION NOTE (layout.overlayGrid): Alternate header for the list of grid container
+# elements if only one item can be selected.
+layout.overlayGrid=Overlay Grid