diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
index ed7de4cc0c5..f24a1eec200 100644
--- a/.github/workflows/deploy.yml
+++ b/.github/workflows/deploy.yml
@@ -16,7 +16,7 @@ jobs:
   package:
     runs-on: ubuntu-latest
     env:
-      SETUPTOOLS_SCM_PRETEND_VERSION: ${{ github.event.inputs.version }}
+      SETUPTOOLS_SCM_PRETEND_VERSION_FOR_PYTEST: ${{ github.event.inputs.version }}
     timeout-minutes: 10
 
     # Required by attest-build-provenance-github.
@@ -55,7 +55,7 @@ jobs:
     - name: Install tox
       run: |
         python -m pip install --upgrade pip
-        pip install --upgrade tox
+        pip install tox
 
     - name: Generate release notes
       env:
diff --git a/.github/workflows/doc-check-links.yml b/.github/workflows/doc-check-links.yml
index 497ec73500a..9de20b37cc3 100644
--- a/.github/workflows/doc-check-links.yml
+++ b/.github/workflows/doc-check-links.yml
@@ -28,7 +28,7 @@ jobs:
           python-version: "3.13"
           cache: pip
 
-      - name: Install dependencies
+      - name: Install tox
         run: |
           python -m pip install --upgrade pip
           pip install tox
diff --git a/.github/workflows/prepare-release-pr.yml b/.github/workflows/prepare-release-pr.yml
index 9dcfea7bae5..94b3dfc7710 100644
--- a/.github/workflows/prepare-release-pr.yml
+++ b/.github/workflows/prepare-release-pr.yml
@@ -38,10 +38,10 @@ jobs:
       with:
         python-version: "3.13"
 
-    - name: Install dependencies
+    - name: Install tox
       run: |
         python -m pip install --upgrade pip
-        pip install --upgrade setuptools tox
+        pip install tox
 
     - name: Prepare release PR (minor/patch release)
       if: github.event.inputs.major == 'no'
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index fbee593f7c2..443a1723a0c 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -268,10 +268,10 @@ jobs:
         check-latest: true
         allow-prereleases: true
 
-    - name: Install dependencies
+    - name: Install tox
       run: |
         python -m pip install --upgrade pip
-        pip install tox coverage
+        pip install tox
 
     - name: Test without coverage
       if: "! matrix.use_coverage"
@@ -283,10 +283,6 @@ jobs:
       shell: bash
       run: tox run -e ${{ matrix.tox_env }}-coverage --installpkg `find dist/*.tar.gz`
 
-    - name: Generate coverage report
-      if: "matrix.use_coverage"
-      run: python -m coverage xml
-
     - name: Upload coverage to Codecov
       if: "matrix.use_coverage"
       uses: codecov/codecov-action@5a1091511ad55cbe89839c7260b706298ca349f7
diff --git a/.github/workflows/update-plugin-list.yml b/.github/workflows/update-plugin-list.yml
index b396d6e19d4..c4d3087f285 100644
--- a/.github/workflows/update-plugin-list.yml
+++ b/.github/workflows/update-plugin-list.yml
@@ -40,7 +40,7 @@ jobs:
       - name: Install tox
         run: |
           python -m pip install --upgrade pip
-          pip install --upgrade tox
+          pip install tox
 
       - name: Update Plugin List
         run: tox -e update-plugin-list
diff --git a/tox.ini b/tox.ini
index 8e760e9e2e2..2ad59f8225e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -65,6 +65,8 @@ commands =
     doctesting: {env:_PYTEST_TOX_COVERAGE_RUN:} pytest --doctest-modules --pyargs _pytest
     coverage: coverage combine
     coverage: coverage report -m
+    # Run `coverage xml` only on CI.
+    coverage: python -c 'import os; os.environ.get("CI") and os.execlp("coverage", "coverage", "xml")'
 passenv =
     COVERAGE_*
     PYTEST_ADDOPTS
@@ -108,7 +110,6 @@ deps =
     twisted25: twisted>=25
     asynctest: asynctest
     xdist: pytest-xdist>=2.1.0
-    xdist: -e .
 # Can use the same wheel for all environments.
 package = wheel
 wheel_build_env = .pkg
@@ -174,9 +175,6 @@ description =
     run reverse dependency testing against pytest plugins under `{basepython}`
 # use latest versions of all plugins, including pre-releases
 pip_pre=true
-# use latest pip to get new dependency resolver (#7783)
-download=true
-install_command=python -m pip install {opts} {packages}
 changedir = testing/plugins_integration
 deps = -rtesting/plugins_integration/requirements.txt
 setenv =