Guided Failure Mode
The guided failure mode is a very nice feature and we use it a lot. One improvement that our Ops guys would like is better visibility on when a failure occurs.
For example, we have 30 steps and as the deploy is progressing the top of the page is not visible.So, when a failure occurs that needs to be addressed you don't really know about it until you scroll to the top, because when the top of the page is off the screen there is nothing that indicates a problem.
The only way you know there's an issue is by...
1) Make sure you keep an eye on the top of the screen, so constantly scroll up and down.
2) Notice that the current step is taking longer than normal and then scroll to the top to see if there is an issue.
Maybe add a floating notification, so no matter what your scroll position is, you can see that a failure occurred. Or, simply auto scroll the page to the top when a failure occurs so it's obvious to what is happening.

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Paul commented
could there also be the option to send an email notification to a pre-defined group of users stating that the release has gone into guided failure mode on "xyz" step.