diff --git a/devtools/client/jsonview/components/JsonToolbar.js b/devtools/client/jsonview/components/JsonToolbar.js
index 877d441e34f7..b60df8d5ba2f 100644
--- a/devtools/client/jsonview/components/JsonToolbar.js
+++ b/devtools/client/jsonview/components/JsonToolbar.js
@@ -73,12 +73,12 @@ define(function(require, exports, module) {
           { className: "btn collapse", onClick: this.onCollapse },
           JSONView.Locale["jsonViewer.CollapseAll"]
         ),
-        this.props.dataSize > EXPAND_THRESHOLD
-          ? undefined
-          : ToolbarButton(
-              { className: "btn expand", onClick: this.onExpand },
-              JSONView.Locale["jsonViewer.ExpandAll"]
-            ),
+        ToolbarButton(
+          { className: "btn expand", onClick: this.onExpand },
+          this.props.dataSize > EXPAND_THRESHOLD
+            ? JSONView.Locale["jsonViewer.ExpandAllSlow"]
+            : JSONView.Locale["jsonViewer.ExpandAll"]
+        ),
         div({ className: "devtools-separator" }),
         SearchBox({
           actions: this.props.actions,
diff --git a/devtools/client/locales/en-US/jsonview.properties b/devtools/client/locales/en-US/jsonview.properties
index b810f730ebd8..6ef5e4e0e3c9 100644
--- a/devtools/client/locales/en-US/jsonview.properties
+++ b/devtools/client/locales/en-US/jsonview.properties
@@ -31,6 +31,7 @@ jsonViewer.Copy=Copy
 
 # LOCALIZATION NOTE (jsonViewer.ExpandAll): Label for expanding all nodes
 jsonViewer.ExpandAll=Expand All
+jsonViewer.ExpandAllSlow=Expand All (slow)
 
 # LOCALIZATION NOTE (jsonViewer.CollapseAll): Label for collapsing all nodes
 jsonViewer.CollapseAll=Collapse All