Previews that copy data no longer fail while being created
Creating a preview with a copy of your data could fail with “the instance failed to restart”, even though nothing was wrong with your hooks or migrations. Each step of setting up the preview restarted it, and on a fast server those restarts came too close together.
A new preview is now started once, after its hooks, migrations, public files and environment variables are all in place. Creating one is faster, and the restart error is gone. A preview that cannot be started is reported as failed rather than ready.