diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index df5ea06..f09781f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -74,7 +74,7 @@ jobs:
             mediawiki
             !mediawiki/extensions/
             !mediawiki/vendor/
-          key: mw_${{ matrix.mw }}-php${{ matrix.php }}
+          key: mw_${{ matrix.mw }}-php${{ matrix.php }}-v2
 
       - name: Cache Composer cache
         uses: actions/cache@v4
@@ -102,14 +102,24 @@ jobs:
         working-directory: ~
         run: bash EarlyCopy/.github/workflows/uploadImages.sh
 
-      - if: env.TYPE != 'coverage'
+      - if: env.TYPE != 'coverage' && matrix.mw != 'master'
         name: Run PHPUnit w/o coverage
         run: php tests/phpunit/phpunit.php -c extensions/BootstrapComponents/ --testsuite bootstrap-components-unit
 
-      - if: env.TYPE == 'coverage'
+      - if: env.TYPE == 'coverage' && matrix.mw != 'master'
         name: Run PHPUnit w/ coverage
         run: php tests/phpunit/phpunit.php -c extensions/BootstrapComponents/ --testsuite bootstrap-components-unit --coverage-clover coverage.clover
 
+      - if: matrix.mw == 'master'
+        name: Run PHPUnit (MW master)
+        run: |
+          # MediaWiki master (≥ 1.46) removed tests/phpunit/phpunit.php; the
+          # supported runner is vendor/bin/phpunit against the config
+          # generated by `composer phpunit:config` from phpunit.xml.template
+          # (which installWiki.sh's git clone ships).
+          composer phpunit:config
+          vendor/bin/phpunit -c extensions/BootstrapComponents/phpunit.xml.dist --bootstrap tests/phpunit/bootstrap.php --testsuite bootstrap-components-unit
+
       - if: env.TYPE == 'coverage'
         name: upload coverage report
         working-directory: ~
diff --git a/.github/workflows/installWiki.sh b/.github/workflows/installWiki.sh
index 62b6662..41d7b53 100644
--- a/.github/workflows/installWiki.sh
+++ b/.github/workflows/installWiki.sh
@@ -4,10 +4,12 @@ MW_BRANCH=$1
 EXTENSION_NAME=$2
 
 ## install core
-wget https://github.com/wikimedia/mediawiki/archive/${MW_BRANCH}.tar.gz -nv
-
-tar -zxf $MW_BRANCH.tar.gz
-mv mediawiki-$MW_BRANCH mediawiki
+# Clone rather than fetch the tarball: MW's .gitattributes marks
+# phpunit.xml.template as `export-ignore`, so it's absent from the
+# archive that GitHub serves. `composer phpunit:config` on MW master
+# needs that file; `git clone` ships it. ~40MB extra in cached
+# `.git/`, no measurable time difference.
+git clone --depth 1 --branch "$MW_BRANCH" https://github.com/wikimedia/mediawiki.git mediawiki
 cd $MW_ROOT
 
 composer install