diff --git a/.github/workflows/reusable-functional.yml b/.github/workflows/reusable-functional.yml
index 3bf0cc6..d1ab1a8 100644
--- a/.github/workflows/reusable-functional.yml
+++ b/.github/workflows/reusable-functional.yml
@@ -25,37 +25,26 @@ on:
         required: false
         default: false
       os:
-        description: 'Runner to use. Defaults to ubuntu-24.04, or the RUNNERS_NAME repository variable when set.'
+        description: 'Runner to use. Defaults to ubuntu-22.04, or the RUNNERS_NAME repository variable when set.'
         type: string
         required: false
         default: ''
-      grouped:
-        description: 'Set when the calling job name already states the suite and PHP version, so this workflow leaves them out instead of repeating them inside the group.'
-        type: boolean
-        required: false
-        default: false
 
 permissions:
   contents: read
 
 jobs:
   functional:
-    # When the caller wraps this workflow, its own name is not surfaced in the run
-    # view, so this name has to carry everything. When the caller fans out, its job
-    # name becomes the group header and already states the suite and PHP version,
-    # so repeating them here reads as noise. `grouped` picks between the two.
-    #
-    # Written as `!grouped && <prefix> || ''` rather than `grouped && '' || <prefix>`
-    # on purpose: an empty string is falsy, so the latter would fall through to the
-    # prefix in both cases.
-    #
-    # The database version is spelled out because "MySQL" alone rendered the
-    # mysql-8.0 and mysql-8.4 legs identically.
-    name: ${{ !inputs.grouped && format('Behat | PHP {0} | ', inputs.php) || '' }}WP ${{ inputs.wp }} | ${{ inputs.dbtype == 'sqlite' && 'SQLite' || inputs.mysql || 'MySQL' }}${{ inputs.object_cache == 'sqlite' && ' (Obj Cache)' || '' }}${{ inputs.coverage && ' (with coverage)' || '' }}${{ startsWith( inputs.os, 'windows' ) && ' (Windows)' || '' }}${{ startsWith( inputs.os, 'macos' ) && ' (macOS)' || '' }}
+    # This name has to stand on its own. The run view labels a nested job with its
+    # own name only; the calling job's name is not surfaced at this depth, so
+    # anything omitted here is not shown anywhere. The database version is spelled
+    # out because "MySQL" alone rendered the mysql-8.0 and mysql-8.4 legs
+    # identically.
+    name: Behat | PHP ${{ inputs.php }} | WP ${{ inputs.wp }} | ${{ inputs.dbtype == 'sqlite' && 'SQLite' || inputs.mysql || 'MySQL' }}${{ inputs.object_cache == 'sqlite' && ' (Obj Cache)' || '' }}${{ inputs.coverage && ' (with coverage)' || '' }}${{ startsWith( inputs.os, 'windows' ) && ' (Windows)' || '' }}${{ startsWith( inputs.os, 'macos' ) && ' (macOS)' || '' }}
     # Repositories with a heavy Behat suite can point the default Linux legs at a
     # larger runner by setting the `RUNNERS_NAME` repository variable, without
     # having to fork this workflow. Explicit macOS/Windows legs are unaffected.
-    runs-on: ${{ inputs.os || vars.RUNNERS_NAME || 'ubuntu-24.04' }}
+    runs-on: ${{ inputs.os || vars.RUNNERS_NAME || 'ubuntu-22.04' }}
 
     continue-on-error: ${{ inputs.dbtype == 'mariadb' || inputs.php == 'nightly' || startsWith( inputs.os, 'windows' ) || startsWith( inputs.os, 'macos' ) }}
 
@@ -107,7 +96,7 @@ jobs:
       # image drops it.
       - name: Install Ghostscript
         # Keyed on the actual runner rather than the `os` input: an empty input no
-        # longer implies the default image now that RUNNERS_NAME can select it.
+        # longer implies ubuntu-22.04 now that RUNNERS_NAME can select the image.
         if: ${{ runner.os == 'Linux' }}
         run: |
           if command -v gs > /dev/null 2>&1; then
@@ -142,22 +131,16 @@ jobs:
           COMPOSER_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Change ImageMagick policy to allow pdf->png conversion.
-        # Keyed on the actual runner rather than the `os` input, and matched by glob
-        # rather than a hardcoded ImageMagick-6 path, so this keeps working if an
-        # image ships ImageMagick 7. `sed -i` on a missing file exits non-zero and
-        # would fail the leg.
+        # Keyed on the actual runner rather than the `os` input, and tolerant of
+        # images that ship a different ImageMagick layout — `sed -i` on a missing
+        # file exits non-zero and would fail the leg.
         if: ${{ runner.os == 'Linux' }}
         run: |
-          shopt -s nullglob
-          POLICIES=(/etc/ImageMagick-*/policy.xml)
-          if [ ${#POLICIES[@]} -eq 0 ]; then
-            echo 'No ImageMagick policy file found; nothing to relax.'
-            exit 0
+          if [ -f /etc/ImageMagick-6/policy.xml ]; then
+            sudo sed -i 's/^.*policy.*coder.*none.*PDF.*//' /etc/ImageMagick-6/policy.xml
+          else
+            echo 'No ImageMagick 6 policy file found; nothing to relax.'
           fi
-          for policy in "${POLICIES[@]}"; do
-            echo "Relaxing the PDF coder policy in ${policy}."
-            sudo sed -i 's/^.*policy.*coder.*none.*PDF.*//' "$policy"
-          done
 
       # WP-CLI packages do not commit a lock file, so `composer update` resolves
       # dependencies on every run while the cache key stays pinned to composer.json.
diff --git a/.github/workflows/reusable-prepare-matrix.yml b/.github/workflows/reusable-prepare-matrix.yml
deleted file mode 100644
index ad82704..0000000
--- a/.github/workflows/reusable-prepare-matrix.yml
+++ /dev/null
@@ -1,520 +0,0 @@
-##
-# Computes the unit and functional test matrices for a package.
-#
-# Split out of reusable-testing.yml so a caller can own the fan-out itself. A
-# matrix only becomes a collapsible group in the Actions run view when it sits on
-# a job declared in the workflow the run belongs to; a matrix one level down is
-# not surfaced. Calling this workflow directly and fanning out from the caller is
-# therefore the only way to group the legs by PHP version.
-#
-# reusable-testing.yml still wraps this for callers that do not need that.
-##
-name: Prepare test matrices
-
-on:
-  workflow_call:
-    inputs:
-      minimum-php:
-        description: 'Minimum PHP version to test against.'
-        type: string
-        required: false
-        default: '7.2'
-      minimum-wp:
-        description: 'Minimum WP version to test against.'
-        type: string
-        required: false
-        default: '4.9'
-      with-coverage:
-        description: 'Include coverage tests.'
-        type: boolean
-        required: false
-        default: true
-      matrix:
-        description: 'Additional matrix entries to include or exclude.'
-        type: string
-        required: false
-        default: '{ "include": [], "exclude": [] }'
-    outputs:
-      unit:
-        description: 'Matrix for the unit test legs as a JSON string, or empty when the package has no PHPUnit setup or the change is documentation only.'
-        value: ${{ jobs.prepare.outputs.unit }}
-      functional:
-        description: 'Matrix for the Behat legs as a JSON string, or empty when the package has no Behat setup or the change is documentation only.'
-        value: ${{ jobs.prepare.outputs.functional }}
-
-permissions:
-  contents: read
-
-jobs:
-  prepare:
-    name: Prepare test matrices
-    runs-on: ubuntu-24.04
-    timeout-minutes: 10
-    outputs:
-      unit: ${{ steps.unit.outputs.matrix }}
-      functional: ${{ steps.functional.outputs.matrix }}
-    steps:
-      - name: Check out source code
-        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
-        with:
-          persist-credentials: false
-          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
-          # Enough history to diff the change against its base. Other events do
-          # not inspect a diff and do not need it. The operands are quoted because
-          # an unquoted 0 is falsy, which would make `&& 0 || 1` always yield 1.
-          fetch-depth: ${{ ( github.event_name == 'pull_request' || github.event_name == 'push' ) && '0' || '1' }}
-
-      # A change that only touches documentation cannot affect the test result, so
-      # there is no reason to spend 50 jobs on it. This is deliberately a deny list
-      # rather than an allow list: the reusable workflow cannot know how any given
-      # package lays out its source, so anything not provably irrelevant still runs
-      # the full suite. Every failure path below also falls back to testing.
-      - name: Determine whether the change is documentation only
-        id: docs-only
-        env:
-          EVENT_NAME: ${{ github.event_name }}
-          BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.before }}
-          HEAD_SHA: ${{ github.event.pull_request.head.sha || github.sha }}
-        run: |
-          # Scheduled and manually dispatched runs always test everything.
-          if [ "$EVENT_NAME" != 'pull_request' ] && [ "$EVENT_NAME" != 'push' ]; then
-            echo 'Not a pull request or push; testing everything.'
-            echo "value=false" >> "$GITHUB_OUTPUT"
-            exit 0
-          fi
-
-          # A newly created branch reports an all-zero base.
-          if [ -z "$BASE_SHA" ] || [ "$BASE_SHA" = '0000000000000000000000000000000000000000' ]; then
-            echo 'No usable base commit; testing everything.'
-            echo "value=false" >> "$GITHUB_OUTPUT"
-            exit 0
-          fi
-
-          if ! CHANGED=$(git diff --name-only "${BASE_SHA}...${HEAD_SHA}" 2>/dev/null); then
-            echo "Could not diff ${BASE_SHA}...${HEAD_SHA}; testing everything."
-            echo "value=false" >> "$GITHUB_OUTPUT"
-            exit 0
-          fi
-
-          echo 'Changed files:'
-          printf '%s\n' "$CHANGED"
-
-          RELEVANT=$(printf '%s\n' "$CHANGED" | grep -Ev \
-            -e '\.md$' \
-            -e '^\.github/ISSUE_TEMPLATE/' \
-            -e '^\.github/(CODEOWNERS|FUNDING\.yml)$' \
-            -e '^(LICENSE|\.editorconfig|\.gitattributes|\.gitignore)$' \
-            || true)
-
-          if [ -z "$RELEVANT" ]; then
-            echo 'Only documentation and repository metadata changed; skipping the test matrix.'
-            echo "value=true" >> "$GITHUB_OUTPUT"
-          else
-            echo 'Test-relevant files changed:'
-            printf '%s\n' "$RELEVANT"
-            echo "value=false" >> "$GITHUB_OUTPUT"
-          fi
-
-      # Entries flagged with "nightly": true are the ones the test jobs run with
-      # `continue-on-error`. They can never gate a merge, so running them on every
-      # pull request spends runner time without producing a signal. They run on the
-      # nightly schedule and on manual dispatch instead.
-      - name: Build the base matrix
-        id: base
-        env:
-          ADDITIONAL_MATRIX: ${{ inputs.matrix }}
-          INCLUDE_NIGHTLY: ${{ github.event_name == 'schedule' || github.event_name == 'workflow_dispatch' }}
-        run: |
-          MATRIX=$(cat << 'EOF'
-          {
-            "include": [
-              {
-                "php": "7.2",
-                "wp": "4.9",
-                "mysql": "mysql-5.6"
-              },
-              {
-                "php": "7.2",
-                "wp": "6.9",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "7.2",
-                "wp": "6.9",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "7.3",
-                "wp": "6.9",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "7.3",
-                "wp": "6.9",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "7.4",
-                "wp": "latest",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "7.4",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.0",
-                "wp": "latest",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.0",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.1",
-                "wp": "latest",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.1",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.2",
-                "wp": "latest",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.2",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.3",
-                "wp": "latest",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.3",
-                "wp": "latest",
-                "mysql": "mysql-8.4"
-              },
-              {
-                "php": "8.3",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.3",
-                "wp": "latest",
-                "mysql": "mariadb-11.4",
-                "dbtype": "mariadb",
-                "nightly": true
-              },
-              {
-                "php": "8.4",
-                "wp": "latest",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.4",
-                "wp": "latest",
-                "mysql": "mysql-8.4"
-              },
-              {
-                "php": "8.4",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.4",
-                "wp": "latest",
-                "mysql": "mariadb-11.4",
-                "dbtype": "mariadb",
-                "nightly": true
-              },
-              {
-                "php": "8.5",
-                "wp": "latest",
-                "mysql": "mysql-8.0",
-                "coverage": true
-              },
-              {
-                "php": "8.5",
-                "wp": "latest",
-                "mysql": "mysql-8.4"
-              },
-              {
-                "php": "8.5",
-                "wp": "latest",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.5",
-                "wp": "latest",
-                "mysql": "mariadb-11.4",
-                "dbtype": "mariadb",
-                "nightly": true
-              },
-              {
-                "php": "7.4",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "7.4",
-                "wp": "trunk",
-                "mysql": "mysql-5.7"
-              },
-              {
-                "php": "7.4",
-                "wp": "trunk",
-                "mysql": "mysql-5.6"
-              },
-              {
-                "php": "8.0",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.0",
-                "wp": "trunk",
-                "mysql": "mysql-5.7"
-              },
-              {
-                "php": "8.0",
-                "wp": "trunk",
-                "mysql": "mysql-5.6"
-              },
-              {
-                "php": "8.1",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.2",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.3",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.3",
-                "wp": "trunk",
-                "mysql": "mysql-8.4"
-              },
-              {
-                "php": "8.3",
-                "wp": "trunk",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.3",
-                "wp": "trunk",
-                "mysql": "mariadb-11.4",
-                "dbtype": "mariadb",
-                "nightly": true
-              },
-              {
-                "php": "8.4",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.4",
-                "wp": "trunk",
-                "mysql": "mysql-8.4"
-              },
-              {
-                "php": "8.4",
-                "wp": "trunk",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.4",
-                "wp": "trunk",
-                "mysql": "mariadb-11.4",
-                "dbtype": "mariadb",
-                "nightly": true
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "mysql": "mysql-8.0"
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "mysql": "mysql-8.4"
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "dbtype": "sqlite"
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "mysql": "mariadb-11.4",
-                "dbtype": "mariadb",
-                "nightly": true
-              },
-              {
-                "php": "nightly",
-                "wp": "trunk",
-                "mysql": "mysql-8.4",
-                "nightly": true
-              },
-              {
-                "php": "nightly",
-                "wp": "trunk",
-                "dbtype": "sqlite",
-                "nightly": true
-              },
-              {
-                "php": "8.5",
-                "wp": "latest",
-                "dbtype": "sqlite",
-                "object_cache": "sqlite"
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "dbtype": "sqlite",
-                "object_cache": "sqlite"
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "dbtype": "sqlite",
-                "os": "macos-latest",
-                "nightly": true
-              },
-              {
-                "php": "8.5",
-                "wp": "trunk",
-                "dbtype": "sqlite",
-                "os": "windows-2022",
-                "nightly": true
-              }
-            ]
-          }
-          EOF
-          )
-          MERGED_MATRIX=$(printf '%s\n%s\n' "$MATRIX" "$ADDITIONAL_MATRIX" | jq -sc \
-            --argjson include_nightly "$INCLUDE_NIGHTLY" '
-            . as $root |
-            (($root[0].exclude // []) + ($root[1].exclude // [])) as $excludes |
-            {
-              include: (
-                (.[0].include + .[1].include | map(if .os == null then .os = "" else . end)) |
-                map(. as $item | select($excludes | any(. as $rule | all($rule|keys[]; $item[.] == $rule[.])) | not)) |
-                unique |
-
-                # Drop the soft-failing entries unless this is a nightly or manual run.
-                # Entries supplied through the `matrix` input have no `nightly` key and
-                # are therefore always kept.
-                map(select($include_nightly or (.nightly // false) == false))
-              )
-            }
-          ')
-          echo "matrix=${MERGED_MATRIX}" >> "$GITHUB_OUTPUT"
-
-      - name: Check existence of composer.json & phpunit.xml.dist files
-        id: check_unit_files
-        run: echo "files_exists=$([ -f composer.json ] && [ -f phpunit.xml.dist ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
-
-      - name: Check existence of composer.json & behat.yml files
-        id: check_functional_files
-        run: echo "files_exists=$([ -f composer.json ] && [ -f behat.yml ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
-
-      - name: Set unit test matrix
-        id: unit
-        env:
-          BASE_MATRIX: ${{ steps.base.outputs.matrix }}
-          FILE_EXISTS: ${{ steps.check_unit_files.outputs.files_exists }}
-          DOCS_ONLY: ${{ steps.docs-only.outputs.value }}
-          INPUTS_MINIMUM_PHP: ${{ inputs.minimum-php }}
-          INPUTS_MINIMUM_WP: ${{ inputs.minimum-wp }}
-          WITH_COVERAGE: ${{ inputs.with-coverage }}
-        run: |
-          if [[ $FILE_EXISTS == 'true' && $DOCS_ONLY != 'true' ]]; then
-            echo "matrix=$(jq -c \
-              --argjson with_coverage_flag "${WITH_COVERAGE}" \
-              --arg minimum_php "${INPUTS_MINIMUM_PHP}" \
-              --arg minimum_wp "${INPUTS_MINIMUM_WP}" \
-              '
-              .include |= (
-                map(
-                  # First, select only the versions that meet all minimum requirements
-                  select(
-                    (.php >= $minimum_php) and
-                    (.wp == "latest" or .wp >= $minimum_wp)
-                  ) |
-
-                  # Next, update the coverage flag on the remaining items
-                  if $with_coverage_flag == false and .coverage == true then
-                    .coverage = false
-                  else
-                    .
-                  end
-                ) |
-
-                # Finally, get the unique entries
-                unique_by([.php, .os])
-              )
-              ' <<< "$BASE_MATRIX")" >> "$GITHUB_OUTPUT"
-          else
-            echo "matrix=" >> "$GITHUB_OUTPUT"
-          fi
-
-      - name: Set functional test matrix
-        id: functional
-        env:
-          BASE_MATRIX: ${{ steps.base.outputs.matrix }}
-          FILE_EXISTS: ${{ steps.check_functional_files.outputs.files_exists }}
-          DOCS_ONLY: ${{ steps.docs-only.outputs.value }}
-          INPUTS_MINIMUM_PHP: ${{ inputs.minimum-php }}
-          INPUTS_MINIMUM_WP: ${{ inputs.minimum-wp }}
-          WITH_COVERAGE: ${{ inputs.with-coverage }}
-        run: |
-          if [[ $FILE_EXISTS == 'true' && $DOCS_ONLY != 'true' ]]; then
-            echo "matrix=$(jq -c \
-              --argjson with_coverage_flag "${WITH_COVERAGE}" \
-              --arg minimum_php "${INPUTS_MINIMUM_PHP}" \
-              --arg minimum_wp "${INPUTS_MINIMUM_WP}" \
-              '
-              # First, select only the versions that meet all minimum requirements
-              .include |= (
-                map(
-                  select(
-                    .php >= $minimum_php
-                  ) |
-                  # Next, update the coverage flag on the remaining items
-                  if $with_coverage_flag == false and .coverage == true then
-                    .coverage = false
-                  else
-                  .
-                  end
-                )
-              ) |
-
-              # Reassign WP4.9 to minimum_wp
-              .include |= (
-                map(
-                  select(
-                    .wp == "4.9"
-                  ).wp |= $minimum_wp
-                )
-              )
-              ' <<< "$BASE_MATRIX" )" >> "$GITHUB_OUTPUT"
-          else
-            echo "matrix=" >> "$GITHUB_OUTPUT"
-          fi
diff --git a/.github/workflows/reusable-testing.yml b/.github/workflows/reusable-testing.yml
index 8caa474..339f994 100644
--- a/.github/workflows/reusable-testing.yml
+++ b/.github/workflows/reusable-testing.yml
@@ -37,16 +37,478 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  # The matrix computation lives in its own reusable workflow so a caller can
-  # invoke it directly and fan out from its own top-level jobs, which is what
-  # makes the legs group by PHP version in the run view. See the README.
   prepare:
-    uses: ./.github/workflows/reusable-prepare-matrix.yml
-    with:
-      minimum-php: ${{ inputs.minimum-php }}
-      minimum-wp: ${{ inputs.minimum-wp }}
-      with-coverage: ${{ inputs.with-coverage }}
-      matrix: ${{ inputs.matrix }}
+    name: Prepare test matrices
+    runs-on: ubuntu-22.04
+    timeout-minutes: 10
+    outputs:
+      unit: ${{ steps.unit.outputs.matrix }}
+      functional: ${{ steps.functional.outputs.matrix }}
+    steps:
+      - name: Check out source code
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
+          # Enough history to diff the change against its base. Other events do
+          # not inspect a diff and do not need it. The operands are quoted because
+          # an unquoted 0 is falsy, which would make `&& 0 || 1` always yield 1.
+          fetch-depth: ${{ ( github.event_name == 'pull_request' || github.event_name == 'push' ) && '0' || '1' }}
+
+      # A change that only touches documentation cannot affect the test result, so
+      # there is no reason to spend 50 jobs on it. This is deliberately a deny list
+      # rather than an allow list: the reusable workflow cannot know how any given
+      # package lays out its source, so anything not provably irrelevant still runs
+      # the full suite. Every failure path below also falls back to testing.
+      - name: Determine whether the change is documentation only
+        id: docs-only
+        env:
+          EVENT_NAME: ${{ github.event_name }}
+          BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.before }}
+          HEAD_SHA: ${{ github.event.pull_request.head.sha || github.sha }}
+        run: |
+          # Scheduled and manually dispatched runs always test everything.
+          if [ "$EVENT_NAME" != 'pull_request' ] && [ "$EVENT_NAME" != 'push' ]; then
+            echo 'Not a pull request or push; testing everything.'
+            echo "value=false" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          # A newly created branch reports an all-zero base.
+          if [ -z "$BASE_SHA" ] || [ "$BASE_SHA" = '0000000000000000000000000000000000000000' ]; then
+            echo 'No usable base commit; testing everything.'
+            echo "value=false" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          if ! CHANGED=$(git diff --name-only "${BASE_SHA}...${HEAD_SHA}" 2>/dev/null); then
+            echo "Could not diff ${BASE_SHA}...${HEAD_SHA}; testing everything."
+            echo "value=false" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          echo 'Changed files:'
+          printf '%s\n' "$CHANGED"
+
+          RELEVANT=$(printf '%s\n' "$CHANGED" | grep -Ev \
+            -e '\.md$' \
+            -e '^\.github/ISSUE_TEMPLATE/' \
+            -e '^\.github/(CODEOWNERS|FUNDING\.yml)$' \
+            -e '^(LICENSE|\.editorconfig|\.gitattributes|\.gitignore)$' \
+            || true)
+
+          if [ -z "$RELEVANT" ]; then
+            echo 'Only documentation and repository metadata changed; skipping the test matrix.'
+            echo "value=true" >> "$GITHUB_OUTPUT"
+          else
+            echo 'Test-relevant files changed:'
+            printf '%s\n' "$RELEVANT"
+            echo "value=false" >> "$GITHUB_OUTPUT"
+          fi
+
+      # Entries flagged with "nightly": true are the ones the test jobs run with
+      # `continue-on-error`. They can never gate a merge, so running them on every
+      # pull request spends runner time without producing a signal. They run on the
+      # nightly schedule and on manual dispatch instead.
+      - name: Build the base matrix
+        id: base
+        env:
+          ADDITIONAL_MATRIX: ${{ inputs.matrix }}
+          INCLUDE_NIGHTLY: ${{ github.event_name == 'schedule' || github.event_name == 'workflow_dispatch' }}
+        run: |
+          MATRIX=$(cat << 'EOF'
+          {
+            "include": [
+              {
+                "php": "7.2",
+                "wp": "4.9",
+                "mysql": "mysql-5.6"
+              },
+              {
+                "php": "7.2",
+                "wp": "6.9",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "7.2",
+                "wp": "6.9",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "7.3",
+                "wp": "6.9",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "7.3",
+                "wp": "6.9",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "7.4",
+                "wp": "latest",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "7.4",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.0",
+                "wp": "latest",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.0",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.1",
+                "wp": "latest",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.1",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.2",
+                "wp": "latest",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.2",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.3",
+                "wp": "latest",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.3",
+                "wp": "latest",
+                "mysql": "mysql-8.4"
+              },
+              {
+                "php": "8.3",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.3",
+                "wp": "latest",
+                "mysql": "mariadb-11.4",
+                "dbtype": "mariadb",
+                "nightly": true
+              },
+              {
+                "php": "8.4",
+                "wp": "latest",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.4",
+                "wp": "latest",
+                "mysql": "mysql-8.4"
+              },
+              {
+                "php": "8.4",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.4",
+                "wp": "latest",
+                "mysql": "mariadb-11.4",
+                "dbtype": "mariadb",
+                "nightly": true
+              },
+              {
+                "php": "8.5",
+                "wp": "latest",
+                "mysql": "mysql-8.0",
+                "coverage": true
+              },
+              {
+                "php": "8.5",
+                "wp": "latest",
+                "mysql": "mysql-8.4"
+              },
+              {
+                "php": "8.5",
+                "wp": "latest",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.5",
+                "wp": "latest",
+                "mysql": "mariadb-11.4",
+                "dbtype": "mariadb",
+                "nightly": true
+              },
+              {
+                "php": "7.4",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "7.4",
+                "wp": "trunk",
+                "mysql": "mysql-5.7"
+              },
+              {
+                "php": "7.4",
+                "wp": "trunk",
+                "mysql": "mysql-5.6"
+              },
+              {
+                "php": "8.0",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.0",
+                "wp": "trunk",
+                "mysql": "mysql-5.7"
+              },
+              {
+                "php": "8.0",
+                "wp": "trunk",
+                "mysql": "mysql-5.6"
+              },
+              {
+                "php": "8.1",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.2",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.3",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.3",
+                "wp": "trunk",
+                "mysql": "mysql-8.4"
+              },
+              {
+                "php": "8.3",
+                "wp": "trunk",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.3",
+                "wp": "trunk",
+                "mysql": "mariadb-11.4",
+                "dbtype": "mariadb",
+                "nightly": true
+              },
+              {
+                "php": "8.4",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.4",
+                "wp": "trunk",
+                "mysql": "mysql-8.4"
+              },
+              {
+                "php": "8.4",
+                "wp": "trunk",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.4",
+                "wp": "trunk",
+                "mysql": "mariadb-11.4",
+                "dbtype": "mariadb",
+                "nightly": true
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "mysql": "mysql-8.0"
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "mysql": "mysql-8.4"
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "dbtype": "sqlite"
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "mysql": "mariadb-11.4",
+                "dbtype": "mariadb",
+                "nightly": true
+              },
+              {
+                "php": "nightly",
+                "wp": "trunk",
+                "mysql": "mysql-8.4",
+                "nightly": true
+              },
+              {
+                "php": "nightly",
+                "wp": "trunk",
+                "dbtype": "sqlite",
+                "nightly": true
+              },
+              {
+                "php": "8.5",
+                "wp": "latest",
+                "dbtype": "sqlite",
+                "object_cache": "sqlite"
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "dbtype": "sqlite",
+                "object_cache": "sqlite"
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "dbtype": "sqlite",
+                "os": "macos-latest",
+                "nightly": true
+              },
+              {
+                "php": "8.5",
+                "wp": "trunk",
+                "dbtype": "sqlite",
+                "os": "windows-2022",
+                "nightly": true
+              }
+            ]
+          }
+          EOF
+          )
+          MERGED_MATRIX=$(printf '%s\n%s\n' "$MATRIX" "$ADDITIONAL_MATRIX" | jq -sc \
+            --argjson include_nightly "$INCLUDE_NIGHTLY" '
+            . as $root |
+            (($root[0].exclude // []) + ($root[1].exclude // [])) as $excludes |
+            {
+              include: (
+                (.[0].include + .[1].include | map(if .os == null then .os = "" else . end)) |
+                map(. as $item | select($excludes | any(. as $rule | all($rule|keys[]; $item[.] == $rule[.])) | not)) |
+                unique |
+
+                # Drop the soft-failing entries unless this is a nightly or manual run.
+                # Entries supplied through the `matrix` input have no `nightly` key and
+                # are therefore always kept.
+                map(select($include_nightly or (.nightly // false) == false))
+              )
+            }
+          ')
+          echo "matrix=${MERGED_MATRIX}" >> "$GITHUB_OUTPUT"
+
+      - name: Check existence of composer.json & phpunit.xml.dist files
+        id: check_unit_files
+        run: echo "files_exists=$([ -f composer.json ] && [ -f phpunit.xml.dist ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
+
+      - name: Check existence of composer.json & behat.yml files
+        id: check_functional_files
+        run: echo "files_exists=$([ -f composer.json ] && [ -f behat.yml ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
+
+      - name: Set unit test matrix
+        id: unit
+        env:
+          BASE_MATRIX: ${{ steps.base.outputs.matrix }}
+          FILE_EXISTS: ${{ steps.check_unit_files.outputs.files_exists }}
+          DOCS_ONLY: ${{ steps.docs-only.outputs.value }}
+          INPUTS_MINIMUM_PHP: ${{ inputs.minimum-php }}
+          INPUTS_MINIMUM_WP: ${{ inputs.minimum-wp }}
+          WITH_COVERAGE: ${{ inputs.with-coverage }}
+        run: |
+          if [[ $FILE_EXISTS == 'true' && $DOCS_ONLY != 'true' ]]; then
+            echo "matrix=$(jq -c \
+              --argjson with_coverage_flag "${WITH_COVERAGE}" \
+              --arg minimum_php "${INPUTS_MINIMUM_PHP}" \
+              --arg minimum_wp "${INPUTS_MINIMUM_WP}" \
+              '
+              .include |= (
+                map(
+                  # First, select only the versions that meet all minimum requirements
+                  select(
+                    (.php >= $minimum_php) and
+                    (.wp == "latest" or .wp >= $minimum_wp)
+                  ) |
+
+                  # Next, update the coverage flag on the remaining items
+                  if $with_coverage_flag == false and .coverage == true then
+                    .coverage = false
+                  else
+                    .
+                  end
+                ) |
+
+                # Finally, get the unique entries
+                unique_by([.php, .os])
+              )
+              ' <<< "$BASE_MATRIX")" >> "$GITHUB_OUTPUT"
+          else
+            echo "matrix=" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: Set functional test matrix
+        id: functional
+        env:
+          BASE_MATRIX: ${{ steps.base.outputs.matrix }}
+          FILE_EXISTS: ${{ steps.check_functional_files.outputs.files_exists }}
+          DOCS_ONLY: ${{ steps.docs-only.outputs.value }}
+          INPUTS_MINIMUM_PHP: ${{ inputs.minimum-php }}
+          INPUTS_MINIMUM_WP: ${{ inputs.minimum-wp }}
+          WITH_COVERAGE: ${{ inputs.with-coverage }}
+        run: |
+          if [[ $FILE_EXISTS == 'true' && $DOCS_ONLY != 'true' ]]; then
+            echo "matrix=$(jq -c \
+              --argjson with_coverage_flag "${WITH_COVERAGE}" \
+              --arg minimum_php "${INPUTS_MINIMUM_PHP}" \
+              --arg minimum_wp "${INPUTS_MINIMUM_WP}" \
+              '
+              # First, select only the versions that meet all minimum requirements
+              .include |= (
+                map(
+                  select(
+                    .php >= $minimum_php
+                  ) |
+                  # Next, update the coverage flag on the remaining items
+                  if $with_coverage_flag == false and .coverage == true then
+                    .coverage = false
+                  else
+                  .
+                  end
+                )
+              ) |
+
+              # Reassign WP4.9 to minimum_wp
+              .include |= (
+                map(
+                  select(
+                    .wp == "4.9"
+                  ).wp |= $minimum_wp
+                )
+              )
+              ' <<< "$BASE_MATRIX" )" >> "$GITHUB_OUTPUT"
+          else
+            echo "matrix=" >> "$GITHUB_OUTPUT"
+          fi
 
   unit:
     needs: prepare
diff --git a/.github/workflows/reusable-unit.yml b/.github/workflows/reusable-unit.yml
index 565cd18..6bcb8f7 100644
--- a/.github/workflows/reusable-unit.yml
+++ b/.github/workflows/reusable-unit.yml
@@ -10,31 +10,24 @@ on:
         required: false
         default: false
       os:
-        description: 'Runner to use. Defaults to ubuntu-24.04, or the RUNNERS_NAME repository variable when set.'
+        description: 'Runner to use. Defaults to ubuntu-22.04, or the RUNNERS_NAME repository variable when set.'
         type: string
         required: false
         default: ''
-      grouped:
-        description: 'Set when the calling job name already states the suite and PHP version, so this workflow leaves them out instead of repeating them inside the group.'
-        type: boolean
-        required: false
-        default: false
 
 permissions:
   contents: read
 
 jobs:
   unit:
-    # See the note on the equivalent name in reusable-functional.yml: `grouped`
-    # picks between a name that stands on its own and one that sits inside a group
-    # header which already states the suite and PHP version. A grouped unit leg is
-    # distinguished only by its runner and whether it collects coverage, so those
-    # suffixes carry the whole name.
-    name: ${{ !inputs.grouped && format('Unit | PHP {0}', inputs.php) || 'PHPUnit' }}${{ inputs.coverage && ' (with coverage)' || '' }}${{ startsWith( inputs.os, 'windows' ) && ' (Windows)' || '' }}${{ startsWith( inputs.os, 'macos' ) && ' (macOS)' || '' }}
+    # This name has to stand on its own. The run view labels a nested job with its
+    # own name only; the calling job's name is not surfaced at this depth, so
+    # anything omitted here is not shown anywhere.
+    name: Unit | PHP ${{ inputs.php }}${{ inputs.coverage && ' (with coverage)' || '' }}${{ startsWith( inputs.os, 'windows' ) && ' (Windows)' || '' }}${{ startsWith( inputs.os, 'macos' ) && ' (macOS)' || '' }}
     # Repositories can point the default Linux legs at a larger runner by setting
     # the `RUNNERS_NAME` repository variable, without having to fork this workflow.
     # Explicit macOS/Windows legs are unaffected.
-    runs-on: ${{ inputs.os || vars.RUNNERS_NAME || 'ubuntu-24.04' }}
+    runs-on: ${{ inputs.os || vars.RUNNERS_NAME || 'ubuntu-22.04' }}
     continue-on-error: ${{ inputs.php == 'nightly' }}
     timeout-minutes: ${{ inputs.coverage && 30 || 15 }}
 
diff --git a/.github/workflows/testing.yml b/.github/workflows/testing.yml
index f917c6e..35d7562 100644
--- a/.github/workflows/testing.yml
+++ b/.github/workflows/testing.yml
@@ -13,63 +13,6 @@ on:
 permissions:
   contents: read
 
-# Lives here rather than in the called workflow, because the fan-out below is
-# owned by this file.
-concurrency:
-  group: ${{ github.workflow }}-${{ github.event_name }}-${{ github.ref }}
-  cancel-in-progress: true
-
-# This repository uses the fanned-out form as the reference implementation for
-# the rest of the organisation, and refers to the workflows by local path so that
-# a pull request here exercises its own changes rather than whatever is on main.
-# Packages adopting this shape use `wp-cli/.github/.github/workflows/...@main`.
-# See the README for what this buys and what it costs.
 jobs:
-  prepare:
-    name: Prepare test matrices
-    uses: ./.github/workflows/reusable-prepare-matrix.yml
-
-  unit:
-    needs: prepare
-    if: ${{ needs.prepare.outputs.unit != '' }}
-    # A matrix only becomes a collapsible group in the run view when it sits on a
-    # job declared in the workflow the run belongs to, which is why this fan-out
-    # is here and not one level down.
-    #
-    # The run view groups legs whose calling job name is identical, so this name
-    # must vary by the dimension being grouped on and collide across every other.
-    # A name that does not vary with the matrix at all does not produce one group;
-    # GitHub appends the matrix combination to disambiguate it, giving one group
-    # per leg labelled "Unit (8.5, latest, mysql-8.0)".
-    name: Unit | PHP ${{ matrix.php }}
-    strategy:
-      fail-fast: false
-      matrix: ${{ fromJson(needs.prepare.outputs.unit) }}
-    uses: ./.github/workflows/reusable-unit.yml
-    secrets: inherit
-    with:
-      php: ${{ matrix.php }}
-      coverage: ${{ matrix.coverage == true }}
-      os: ${{ matrix.os || '' }}
-      # The job name above already states the suite and PHP version.
-      grouped: true
-
-  functional:
-    needs: prepare
-    if: ${{ needs.prepare.outputs.functional != '' }}
-    name: Behat | PHP ${{ matrix.php }}
-    strategy:
-      fail-fast: false
-      matrix: ${{ fromJson(needs.prepare.outputs.functional) }}
-    uses: ./.github/workflows/reusable-functional.yml
-    secrets: inherit
-    with:
-      php: ${{ matrix.php }}
-      wp: ${{ matrix.wp }}
-      dbtype: ${{ matrix.dbtype || 'mysql' }}
-      mysql: ${{ matrix.mysql || '' }}
-      object_cache: ${{ matrix.object_cache }}
-      coverage: ${{ matrix.coverage == true }}
-      os: ${{ matrix.os || '' }}
-      # The job name above already states the suite and PHP version.
-      grouped: true
+  test:
+    uses: wp-cli/.github/.github/workflows/reusable-testing.yml@main
diff --git a/README.md b/README.md
index e2142b4..2ebbd65 100644
--- a/README.md
+++ b/README.md
@@ -19,72 +19,6 @@ This repository contains reusable GitHub Actions workflows that are automaticall
 - **Regenerate README** (`regenerate-readme.yml`) - Automatically regenerates README.md files from source
 - **Check Branch Alias** (`check-branch-alias.yml`) - Monitors and updates Composer branch-alias configuration
 
-#### Test workflows
-
-A package's `testing.yml` can call the test workflows in one of two shapes.
-
-The **wrapped** shape is the default and needs three lines:
-
-```yaml
-jobs:
-  test:
-    uses: wp-cli/.github/.github/workflows/reusable-testing.yml@main
-    with:
-      minimum-php: '8.0'
-```
-
-The **fanned-out** shape calls `reusable-prepare-matrix.yml` for the matrix and
-runs the legs from the package's own jobs. See this repository's own
-`testing.yml` for a complete example.
-
-The only thing it buys is presentation: a matrix becomes a collapsible group in
-the Actions run view only when it sits on a job declared in the workflow the run
-belongs to. In the wrapped shape the matrix is one level down and is not
-surfaced, so all fifty legs appear as one flat list. Fanning out puts the matrix
-at the top level, so the run view collapses to one entry per PHP version.
-
-It costs about thirty lines in a file that is not synced, so every future change
-to the fan-out has to be repeated in each package that adopts it. Prefer the
-wrapped shape unless a package has a large enough matrix that the flat list is
-genuinely hard to read.
-
-A fanned-out caller should pass `grouped: true` to `reusable-unit.yml` and
-`reusable-functional.yml`, so their job names leave out what the group header
-already states. Without it the legs read `Behat | PHP 8.5 | WP latest | SQLite`
-inside a group already called `Behat | PHP 8.5`.
-
-The run view groups legs whose calling job name is identical, so that name must
-vary by the dimension being grouped on and collide across every other one. Group
-both suites by PHP version:
-
-```
-Behat | PHP 8.5                    <- the calling job
-  WP latest | mysql-8.0            <- the called workflow, with grouped: true
-  WP trunk  | SQLite
-
-Unit | PHP 8.5
-  PHPUnit (with coverage)
-  PHPUnit (macOS)
-  PHPUnit (Windows)
-```
-
-A name that does not vary with the matrix does not collapse the legs into one
-group. GitHub appends the matrix combination to disambiguate it, so `name: Unit`
-produces one group per leg, labelled `Unit (8.5, latest, mysql-8.0)`.
-
-Some groups will hold a single leg — on a pull request there is one unit leg per
-PHP version, because the macOS and Windows entries only run on the nightly
-schedule. That is expected and still reads better than the alternative.
-
-Wrapped callers must leave `grouped` at its default of `false`, because there is
-no group header for them and the name has to stand on its own.
-
-The one thing to watch is that with `grouped: true` a leg name is only unique
-within its group — `WP latest | SQLite` occurs under every PHP version. That is
-fine wherever the group header is part of the name, which is how the run view and
-the checks list both render it. If a leg ever shows up somewhere without its
-group, set `grouped: false` for that caller and the full name comes back.
-
 #### Branch Alias Checker
 
 The branch alias checker workflow automatically ensures that the Composer `branch-alias` in each repository's `composer.json` is up-to-date. It: