diff --git a/.github/workflows/build-pipdeptree.yml b/.github/workflows/build-pipdeptree.yml
index 4ca6472c1ddb..8dfc3b23b16d 100644
--- a/.github/workflows/build-pipdeptree.yml
+++ b/.github/workflows/build-pipdeptree.yml
@@ -88,8 +88,9 @@ jobs:
           # --graph-output/--output=graphviz-* shell out to the `dot` binary.
           CIBW_BEFORE_TEST_LINUX: dnf -y install graphviz
           # pytest-cov pulls in coverage: test_render_explicit_extras renders pluggy's
-          # "testing" extra, which lists coverage as a requirement.
-          CIBW_TEST_REQUIRES: pytest pytest-cov
+          # "testing" extra, which lists coverage as a requirement. pluggy 1.7.0 dropped
+          # its extras, so older pipdeptree tests need an earlier pluggy.
+          CIBW_TEST_REQUIRES: pytest pytest-cov pluggy<1.7
           CIBW_TEST_SOURCES: tests docs
           # tests/test_build_version.py (new after 4.2.3) reads build.rs/tools/version.py off the
           # project root and a scratch git repo to check the version-derivation tooling itself;
diff --git a/docs/packages/pipdeptree.yaml b/docs/packages/pipdeptree.yaml
index 1c231968c724..b6c2068edf9b 100644
--- a/docs/packages/pipdeptree.yaml
+++ b/docs/packages/pipdeptree.yaml
@@ -40,3 +40,5 @@ versions:
     requires-python: '>=3.10'
 - version: 4.2.6
 - version: 4.2.7
+- version: 4.2.8
+- version: 4.2.9