diff --git a/test/image/baselines/hist_grouped.png b/test/image/baselines/hist_grouped.png
index afe4759741f..a5d9e71a794 100644
Binary files a/test/image/baselines/hist_grouped.png and b/test/image/baselines/hist_grouped.png differ
diff --git a/test/image/baselines/hist_stacked.png b/test/image/baselines/hist_stacked.png
index 6c549fc6817..72cb9a5ec04 100644
Binary files a/test/image/baselines/hist_stacked.png and b/test/image/baselines/hist_stacked.png differ
diff --git a/test/image/mocks/hist_grouped.json b/test/image/mocks/hist_grouped.json
index 6c1a7a6ade1..e41f2042a2b 100644
--- a/test/image/mocks/hist_grouped.json
+++ b/test/image/mocks/hist_grouped.json
@@ -1,10 +1,10 @@
 {
     "data":[{
-        "x":["1","2","3","4"],
-        "type":"histogram"
-    },{
-        "x":["1","2","3","4"],
-        "type":"histogram"
+        "x": [1, 1, 1, 2, 2],
+        "type": "histogram"
+    }, {
+        "x": [1, 2, 3, 4],
+        "type": "histogram"
     }],
-    "layout":{"height":300,"width":400}
+    "layout": {"height": 300, "width": 400}
 }
diff --git a/test/image/mocks/hist_stacked.json b/test/image/mocks/hist_stacked.json
index 59b3c32d640..5588ec4989e 100644
--- a/test/image/mocks/hist_stacked.json
+++ b/test/image/mocks/hist_stacked.json
@@ -1,10 +1,10 @@
 {
-    "data":[{
-        "x":["1","2","3","4"],
-        "type":"histogram"
-    },{
-        "x":["1","2","3","4"],
-        "type":"histogram"
+    "data": [{
+        "x": [1, 1, 1, 2, 2],
+        "type": "histogram"
+    }, {
+        "x": [1, 2, 3, 4],
+        "type": "histogram"
     }],
-    "layout":{"height":300,"width":400,"barmode":"stack"}
+    "layout": {"height": 300, "width": 400, "barmode": "stack"}
 }