Checking for errors in browsers


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By default browsers don't display any error messages when things go wrong. This is so your experience browsing the web is smooth and not interrupted with lots of annoying error messages. However, if something goes wrong with your Construct game, you won't see any error message at first. This can make it difficult to work out what has gone wrong.

To see error messages, you first have to open the browser's Developer Tools and view the console. The console is basically a log of messages and it will list any errors that occurred. These error messages are very useful to add to bug reports! It's also a good idea to check for errors after publishing your game to ensure it is working properly. If something is going wrong, it's also a good place to check in case it lists an error message that wasn't displayed anywhere else.

Opening developer tools

To open developer tools in each browser:

  • In Chrome, Firefox and Edge: press F12
  • Safari: press + + I

Make sure you switch to the Console tab if it's not already showing. This is where any information, warning or error messages will be logged.

Checking for errors on mobile devices

It's tricker to get to developer tools for Android and iOS devices, because you can't bring it up on the device itself. Instead you need to connect it up to a desktop system using its cable, and configure it to allow debugging.

For more information on this see the following guides:

Get Started with Remote Debugging Android Devices - the section on remote debugging WebViews also applies to Android apps.

For iOS refer to the Safari developer tools documentation. As with Android, the same approach can be used to bring up developer tools for iOS apps.

Common errors

Blank screen when running project
Something has gone wrong while loading - use the shortcuts above to find any error message. You might want to post a bug report including the error message.
Game freezes half way through
Something has gone wrong during the game - use the shortcuts above to find any error message. You might want to post a bug report including the error message.
Game works in preview but not after exporting
This is usually caused by broken third-party plugins and behaviors which do not work with the minifier. The error message will probably include random characters like is undefined. Try removing third party plugins or behaviors. You should report the problem to the plugin or behavior developer, since Scirra cannot fix it. If you are not using any third party plugins or behaviors at all, you should post a bug report. As a temporary work-around, you can disable minifying script on export, but please report the bug so it can be fixed.
No audio plays, or sound files come up as '404 not found'
Make sure you've set up all the right MIME types on your server to ensure audio playback works correctly.
Some other files come up as 404 not found
Did you upload the entire project and all its files and folders? You might have forgot to upload everything. You might also want to double-check your server has the right MIME types set up.

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  • What about uploading files on Chromebook that has an error (I don't have the F#-Keys)

  • There's another error, when you install an APK from a website that contains a game created in C3 it doesn't download to work offline, you always need to have active internet conection to make the game works.

    I upload my game on Netlify service and everything goes good, until I try to save the game on cache to play it offline

    P.D: My website is https certificated.

      • [-] [+]
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      • Ashley's avatar
      • Ashley
      • Construct Team Founder
      • 1 points
      • (0 children)

      Android apps (APKs) definitely work offline - they don't actually load anything from the Internet.