Debugging render failures
Since JavaScript code is executing, it may happen that a render may due to an exception. Here are general tips to troubleshoot the issue.
By enabling more detailed logging, all console.log statements from your code will be made visible alongside other debugging information.
From the CLI: Add the --log=verbose flag to your render command.
From Node.JS: Add the verbose: true and dumpBrowserLogs: true options to renderMedia().
If you see a log multiple times, it is because the render is split up to multiple threads. Set --concurrency=1 temporarily to only see each log once.
Use console.log in your code to understand the order things are executing in and verify your assumptions about how your code should behave.
Remove components until the video is empty. At which point does the error disappear? This can help you identify the component responsible for the render failure.
It's also helpful to check for issues on GitHub to see if other people have encountered similar problems. If you find an issue that matches your problem, you can add a comment to the issue to help the community troubleshoot the problem.
Also search the documentation which has over 300 pages and contains troubleshooting instructions for many common problems.
You can ask for help on GitHub and Discord. Read on to see how to get help!