Currently Harbormaster gracefully handles the scenario where the build step implementation no longer exists by displaying "This step has an invalid implementation". This allows the user to fix the issue by deleting the problematic build steps.
However, when one of the valid build steps has an input artifact, the page crashes and the user is unable to resolve the issue (they can not access the "delete step" button):
- Create a Harbormaster build plan with a mix of build steps, where some of them have input artifacts.
- To simulate an extension removing an implementation, delete one of the build step implementations in src/applications/harbormaster/step.
- Observe hard crash.
Harbormaster at least renders the page so the user can delete the broken steps.