Should developer wait for CI pipeline to complete or start next task after pushing
Sit and watch the pipeline run?


No, that is not how you work efficiently.

Developers push their commits to the source control repository and then the CI/CD pipeline is triggered.

Developers may post a well-written pull request anytime they want. There is usually a visual mark representing an "on-going build"/"failed build"/"successful build".

Typically a brach can be merged whenever all these criteria is fulfilled:


at least one approver / or as many that is required to approve has approved.
a "successful build"
no unresolved merge conflicts


If any of these criteria not is fulfilled, they need to be fixed, but the developer does it whenever he has time or priority to do this task.