Got it. We actually see double in the pipeline UI but definitely not in the yaml.
Should we post the yaml here or just open a ticket and follow up with support?
Meanwhile, in both examples you shared links for, I can see that none of the stages had any steps in parallel. While the step we want to use the approval in is serial, there are steps from previous stages that are parallel. Could that be a possible reason for our issue?
Created a bug ticket here anyways => Duplicate steps in UI for pipeline after adding approval step