Currently, using ‘continue-on-error:’ in a step flags the step with a green check and allows the job to continue. The only way to see if the step failed is to look at the step’s log.
Other CI systems allow the UI indication of the failure to propagate up to the job level, so it’s easy to see if the there was an ‘allowed failure’.
Since ‘continue-on-error:’ is step scoped, it would be helpful to have something similar to ‘allow-failure’ at the job level, and have the job level UI indication reflect whether there was a failure.
I suspect normal use would use an expression based on matrix values.
A common use of ‘allow-failure’ is to test ‘packages’ against their respective language’s master branch.