Confusing coverage report on pull request

Description

The top says “Awesome! No coverage changes when comparing this file” but on the right it shows a decline in coverage for jsonc.go of 30%. The message at the top is correct as far as I can tell, but not the coverage change number.

Repository

Steps to Reproduce

Visit the link.

Expected behavior: It should not mention jsonc.go at all since it has nothing to do with this pull request (as far as I can tell).

Actual behavior: It does mention jsonc.go and reports a decline in coverage for this file.

Flakiness? Unclear at this point.

Versions

I’m seeing this on Mac OS with Chrome, but I don’t think that matters.