diff --git a/jupyter_resource_usage/__init__.py b/jupyter_resource_usage/__init__.py
index 4bb82b3..64847ee 100644
--- a/jupyter_resource_usage/__init__.py
+++ b/jupyter_resource_usage/__init__.py
@@ -35,4 +35,6 @@ def _jupyter_nbextension_paths():
     ]
 
 
-load_jupyter_server_extension = load_jupyter_server_extension
+# For backward compatibility
+_load_jupyter_server_extension = load_jupyter_server_extension
+_jupyter_server_extension_paths = _jupyter_server_extension_points
diff --git a/jupyter_resource_usage/static/main.js b/jupyter_resource_usage/static/main.js
index 0a1e6f5..8349037 100644
--- a/jupyter_resource_usage/static/main.js
+++ b/jupyter_resource_usage/static/main.js
@@ -74,7 +74,7 @@ define([
 
                 // Handle CPU display
                 var cpuPercent = data['cpu_percent'];
-                if (cpuPercent) {
+                if (cpuPercent !== undefined) {
                     // Remove hide CSS class if the metrics API gives us a CPU percent to display
                     $('#jupyter-resource-usage-display-cpu').removeClass('jupyter-resource-usage-hide');
                     var maxCpu = data['cpu_count'];