diff --git a/lib/commands/screenshot.js b/lib/commands/screenshot.js
index 501db727b..b7464d6c8 100644
--- a/lib/commands/screenshot.js
+++ b/lib/commands/screenshot.js
@@ -83,7 +83,8 @@ export async function mobileScreenshots(opts = {}) {
     );
 
   const {displayId} = opts;
-  const displayIdStr = _.isNaN(displayId) ? null : `${displayId}`;
+  // @ts-ignore isNaN works properly here
+  const displayIdStr = isNaN(displayId) ? null : `${displayId}`;
   if (displayIdStr) {
     if (!infos[displayIdStr]) {
       throw new Error(