This is more to note the regression than an issue to can be solved in this repo, other than rolling back the PR - looks like some of the diff output messages aren't controlled by the color options - https://github.com/facebook/jest/blob/4bd3d4a05999170f423f7050d4e0537648499e88/packages/jest-diff/src/constants.ts#L10-L11 `jest-diff` is using `chalk.dim` directly, rather than making use of the `commonColor` option which we're turning off when color is set to `false` (from PR #123). The issue I'm seeing after upgrading is that we're getting a diff with color codes when running Jest normally (no colors when running `CI=true`) 