Improved HTML-to-PDF rendering

We've just rolled out some major improvements to our HTML-to-PDF rendering pipeline, so rendering PDFs will be faster, more reliable, and more secure. We can now run many more HTML-to-PDF jobs in parallel, so large submission batches should complete much more quickly.

We have carefully tested these changes before rolling them out and are closely monitoring our metrics and logs. Please contact support if you notice any issues with HTML templates.