diff --git a/.github/workflows/reusable-code-quality.yml b/.github/workflows/reusable-code-quality.yml
index b1a4de7..5d1a81f 100644
--- a/.github/workflows/reusable-code-quality.yml
+++ b/.github/workflows/reusable-code-quality.yml
@@ -23,35 +23,48 @@ jobs:
   actionlint:
     name: Lint GitHub Actions workflows
     runs-on: ubuntu-latest
+    timeout-minutes: 5
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Add problem matcher
         run: |
-          curl -s -o .github/actionlint-matcher.json https://raw.githubusercontent.com/rhysd/actionlint/main/.github/actionlint-matcher.json
+          curl --fail --silent --show-error -o .github/actionlint-matcher.json https://raw.githubusercontent.com/rhysd/actionlint/main/.github/actionlint-matcher.json
           echo "::add-matcher::.github/actionlint-matcher.json"
 
+      # Pinned by digest rather than `:latest`, so the linter cannot change
+      # underneath ~45 repositories without a commit here, and so the image layer
+      # can be reused instead of re-resolved on every run.
       - name: Check workflow files
-        uses: docker://rhysd/actionlint:latest
+        uses: docker://rhysd/actionlint@sha256:5457037ba91acd225478edac3d4b32e45cf6c10291e0dabbfd2491c63129afe1 # v1.7.11
         with:
           args: -color -shellcheck=
 
   lint:
     name: Lint PHP files
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Check existence of composer.json file
         id: check_composer_file
         run: echo "files_exists=$(test -f composer.json && echo true || echo false)" >> "$GITHUB_OUTPUT"
 
+      # See the note on the equivalent step in reusable-unit.yml: no lock file is
+      # committed, so the cache key must be rotated on a schedule.
+      - name: Determine the weekly Composer cache suffix
+        id: composer-cache-suffix
+        run: echo "value=$(date -u +%Y-%W)" >> "$GITHUB_OUTPUT"
+
       - name: Set up PHP environment
         if: steps.check_composer_file.outputs.files_exists == 'true'
         uses: shivammathur/setup-php@f3e473d116dcccaddc5834248c87452386958240 # v2
@@ -65,6 +78,8 @@ jobs:
       - name: Install Composer dependencies & cache dependencies
         if: steps.check_composer_file.outputs.files_exists == 'true'
         uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
+        with:
+          custom-cache-suffix: ${{ steps.composer-cache-suffix.outputs.value }}
         env:
           COMPOSER_ROOT_VERSION: dev-${{ github.event.repository.default_branch }}
 
@@ -98,29 +113,37 @@ jobs:
   lint-gherkin:
     name: Lint Gherkin Feature files
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Setup node
         uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v6
+        with:
+          node-version: 'lts/*'
 
+      # `--fail` matters here: without it curl happily writes an error page to the
+      # config file and the linter then runs against garbage rules.
       - name: Download lint rules
-        run: curl https://raw.githubusercontent.com/wp-cli/.github/refs/heads/main/.gherkin-lintrc -o $RUNNER_TEMP/.gherkin-lintrc
+        run: curl --fail --silent --show-error https://raw.githubusercontent.com/wp-cli/.github/refs/heads/main/.gherkin-lintrc -o "$RUNNER_TEMP/.gherkin-lintrc"
 
       - name: Run linter
-        run: npx --yes gherkin-lint -c $RUNNER_TEMP/.gherkin-lintrc
+        run: npx --yes gherkin-lint -c "$RUNNER_TEMP/.gherkin-lintrc"
 
   lint-spellcheck:
     name: Spell check
     runs-on: ubuntu-latest
+    timeout-minutes: 5
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Check existence of config file
         id: check_files
@@ -133,17 +156,25 @@ jobs:
   phpcs:
     name: PHPCS
     runs-on: ubuntu-latest
+    timeout-minutes: 15
 
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Check existence of composer.json & phpcs.xml.dist files
         id: check_files
         run: echo "files_exists=$([ -f composer.json ] && [ -f phpcs.xml.dist ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
 
+      # See the note on the equivalent step in reusable-unit.yml: no lock file is
+      # committed, so the cache key must be rotated on a schedule.
+      - name: Determine the weekly Composer cache suffix
+        id: composer-cache-suffix
+        run: echo "value=$(date -u +%Y-%W)" >> "$GITHUB_OUTPUT"
+
       - name: Set up PHP environment
         if: steps.check_files.outputs.files_exists == 'true'
         uses: shivammathur/setup-php@f3e473d116dcccaddc5834248c87452386958240 # v2
@@ -156,6 +187,8 @@ jobs:
       - name: Install Composer dependencies & cache dependencies
         if: steps.check_files.outputs.files_exists == 'true'
         uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
+        with:
+          custom-cache-suffix: ${{ steps.composer-cache-suffix.outputs.value }}
         env:
           COMPOSER_ROOT_VERSION: dev-${{ github.event.repository.default_branch }}
 
@@ -177,17 +210,25 @@ jobs:
   phpstan:
     name: PHPStan
     runs-on: ubuntu-latest
+    timeout-minutes: 15
 
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Check existence of composer.json file
         id: check_files
         run: echo "files_exists=$(test -f composer.json && echo true || echo false)" >> "$GITHUB_OUTPUT"
 
+      # See the note on the equivalent step in reusable-unit.yml: no lock file is
+      # committed, so the cache key must be rotated on a schedule.
+      - name: Determine the weekly Composer cache suffix
+        id: composer-cache-suffix
+        run: echo "value=$(date -u +%Y-%W)" >> "$GITHUB_OUTPUT"
+
       - name: Set up PHP environment
         if: steps.check_files.outputs.files_exists == 'true'
         uses: shivammathur/setup-php@f3e473d116dcccaddc5834248c87452386958240 # v2
@@ -200,10 +241,11 @@ jobs:
       - name: Install Composer dependencies & cache dependencies
         if: steps.check_files.outputs.files_exists == 'true'
         uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
+        with:
+          custom-cache-suffix: ${{ steps.composer-cache-suffix.outputs.value }}
         env:
           COMPOSER_ROOT_VERSION: dev-${{ github.event.repository.default_branch }}
 
-
       - name: Check existence of vendor/bin/phpstan file
         id: check_phpstan_binary_file
         run: echo "files_exists=$(test -f vendor/bin/phpstan && echo true || echo false)" >> "$GITHUB_OUTPUT"
diff --git a/.github/workflows/reusable-functional.yml b/.github/workflows/reusable-functional.yml
index 5beb62a..48c1fe5 100644
--- a/.github/workflows/reusable-functional.yml
+++ b/.github/workflows/reusable-functional.yml
@@ -25,20 +25,30 @@ on:
         required: false
         default: false
       os:
+        description: 'Runner to use. Defaults to ubuntu-22.04, or the RUNNERS_NAME repository variable when set.'
         type: string
         required: false
-        default: 'ubuntu-22.04'
+        default: ''
 
 permissions:
   contents: read
 
 jobs:
   functional:
-    name: Behat | PHP ${{ inputs.php }} | WP ${{ inputs.wp }} | ${{ inputs.dbtype == 'sqlite' && 'SQLite' || inputs.dbtype == 'mariadb' && 'MariaDB' || 'MySQL' }}${{ inputs.object_cache == 'sqlite' && ' (Obj Cache)' || '' }}${{ inputs.coverage && ' (with coverage)' || '' }}${{ startsWith( inputs.os, 'windows' ) && ' (Windows)' || '' }}${{ startsWith( inputs.os, 'macos' ) && ' (macOS)' || '' }}
-    runs-on: ${{ inputs.os || 'ubuntu-22.04' }}
+    # The calling job already states "Behat | PHP x" and groups on it, so this only
+    # needs to identify the leg within that group. The database version is spelled
+    # out because "MySQL" alone rendered the mysql-8.0 and mysql-8.4 legs
+    # identically.
+    name: 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-22.04' }}
 
     continue-on-error: ${{ inputs.dbtype == 'mariadb' || inputs.php == 'nightly' || startsWith( inputs.os, 'windows' ) || startsWith( inputs.os, 'macos' ) }}
 
+    timeout-minutes: ${{ ( startsWith( inputs.os, 'windows' ) || startsWith( inputs.os, 'macos' ) ) && 120 || inputs.coverage && 90 || 60 }}
+
     env:
       MYSQL_HOST: 127.0.0.1
       MYSQL_TCP_PORT: 3306
@@ -77,10 +87,21 @@ jobs:
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
+      # Ghostscript ships with the GitHub-hosted images, so the `apt-get update`
+      # this used to run unconditionally cost every Behat leg ~25s for a package
+      # that was already there. Keep the install as a fallback in case a future
+      # image drops it.
       - name: Install Ghostscript
-        if: ${{ inputs.os == 'ubuntu-22.04' || inputs.os == '' }}
+        # Keyed on the actual runner rather than the `os` input: an empty input no
+        # 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
+            echo "Ghostscript $(gs --version) is already installed; skipping."
+            exit 0
+          fi
           sudo apt-get update
           sudo apt-get install ghostscript -y
 
@@ -90,7 +111,12 @@ jobs:
 
       - name: Install dependencies (macOS)
         if: ${{ startsWith(inputs.os, 'macos') }}
-        run: brew install ghostscript
+        run: |
+          if command -v gs > /dev/null 2>&1; then
+            echo "Ghostscript $(gs --version) is already installed; skipping."
+            exit 0
+          fi
+          brew install ghostscript
 
       - name: Set up PHP environment
         uses: shivammathur/setup-php@f3e473d116dcccaddc5834248c87452386958240 # v2
@@ -104,12 +130,31 @@ jobs:
           COMPOSER_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Change ImageMagick policy to allow pdf->png conversion.
-        if: ${{ inputs.os == 'ubuntu-22.04' || inputs.os == '' }}
+        # 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: ${{ runner.os == 'Linux' }}
         run: |
-          sudo sed -i 's/^.*policy.*coder.*none.*PDF.*//' /etc/ImageMagick-6/policy.xml
+          if [ -f /etc/ImageMagick-6/policy.xml ]; then
+            sudo sed -i 's/^.*policy.*coder.*none.*PDF.*//' /etc/ImageMagick-6/policy.xml
+          else
+            echo 'No ImageMagick 6 policy file found; nothing to relax.'
+          fi
+
+      # WP-CLI packages do not commit a lock file, so `composer update` resolves
+      # dependencies on every run while the cache key stays pinned to composer.json.
+      # Rotating the suffix weekly stops `dev-*` requirements from being served out
+      # of an indefinitely stale cache. `%Y-%W` is portable across the GNU, BSD and
+      # Git-for-Windows implementations of `date`.
+      - name: Determine the weekly Composer cache suffix
+        id: composer-cache-suffix
+        shell: bash
+        run: echo "value=$(date -u +%Y-%W)" >> "$GITHUB_OUTPUT"
 
       - name: Install Composer dependencies & cache dependencies
         uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
+        with:
+          custom-cache-suffix: ${{ steps.composer-cache-suffix.outputs.value }}
         env:
           COMPOSER_ROOT_VERSION: dev-${{ github.event.repository.default_branch }}
 
diff --git a/.github/workflows/reusable-testing.yml b/.github/workflows/reusable-testing.yml
index 71700a7..ff2b541 100644
--- a/.github/workflows/reusable-testing.yml
+++ b/.github/workflows/reusable-testing.yml
@@ -29,335 +29,416 @@ permissions:
 
 # Cancels all previous workflow runs for the same branch that have not yet completed.
 concurrency:
-  # The concurrency group contains the workflow name and the branch name.
-  group: ${{ github.workflow }}-${{ github.ref }}
+  # Keying on the ref lets a new push supersede the run it replaces, for pull
+  # requests and branches alike. Keying on the event as well keeps a push to the
+  # default branch and the nightly schedule from cancelling each other, since
+  # both report the same ref.
+  group: ${{ github.workflow }}-${{ github.event_name }}-${{ github.ref }}
   cancel-in-progress: true
 
 jobs:
-  get-matrix:
-    name: Get base test matrix
+  prepare:
+    name: Prepare test matrices
     runs-on: ubuntu-22.04
+    timeout-minutes: 10
     outputs:
-      matrix: ${{ steps.base-matrix.outputs.matrix }}
-    steps:
-    - name: Set matrix
-      id: base-matrix
-      env:
-        ADDITIONAL_MATRIX: ${{ inputs.matrix }}
-      run: |
-        MATRIX=$(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"
-            },
-            {
-              "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"
-            },
-            {
-              "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"
-            },
-            {
-              "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": "7.4",
-              "wp": "trunk",
-              "mysql": "mysql-8.0"
-            },
-            {
-              "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"
-            },
-            {
-              "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"
-            },
-            {
-              "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"
-            },
-            {
-              "php": "nightly",
-              "wp": "trunk",
-              "mysql": "mysql-8.4"
-            },
-            {
-              "php": "nightly",
-              "wp": "trunk",
-              "dbtype": "sqlite"
-            },
-            {
-              "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"
-            },
-            {
-              "php": "8.5",
-              "wp": "trunk",
-              "dbtype": "sqlite",
-              "os": "windows-2022"
-            }
-          ]
-        }
-        EOF
-        )
-        MERGED_MATRIX=$(echo "$MATRIX" "$ADDITIONAL_MATRIX" | jq -s '
-          . 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[.] == $rule[.])) | not)) |
-              unique
-            )
-          }
-        ')
-        echo matrix=$MERGED_MATRIX >> $GITHUB_OUTPUT
-
-  prepare-unit:
-    name: Prepare matrix for unit tests
-    needs: get-matrix
-    runs-on: ubuntu-22.04
-    outputs:
-      matrix: ${{ steps.set-matrix.outputs.matrix }}
+      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_files
+        id: check_unit_files
         run: echo "files_exists=$([ -f composer.json ] && [ -f phpunit.xml.dist ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
 
-      - name: Set matrix
-        id: set-matrix
+      - 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' ]]; then
+          if [[ $FILE_EXISTS == 'true' && $DOCS_ONLY != 'true' ]]; then
             echo "matrix=$(jq -c \
-              --argjson with_coverage_flag "${{ inputs.with-coverage }}" \
+              --argjson with_coverage_flag "${WITH_COVERAGE}" \
               --arg minimum_php "${INPUTS_MINIMUM_PHP}" \
               --arg minimum_wp "${INPUTS_MINIMUM_WP}" \
               '
@@ -380,52 +461,24 @@ jobs:
                 # Finally, get the unique entries
                 unique_by([.php, .os])
               )
-              ' <<< "$BASE_MATRIX")" >> $GITHUB_OUTPUT
+              ' <<< "$BASE_MATRIX")" >> "$GITHUB_OUTPUT"
           else
-            echo "matrix=" >> $GITHUB_OUTPUT
+            echo "matrix=" >> "$GITHUB_OUTPUT"
           fi
+
+      - name: Set functional test matrix
+        id: functional
         env:
-          BASE_MATRIX: ${{ needs.get-matrix.outputs.matrix }}
-          FILE_EXISTS: ${{ steps.check_files.outputs.files_exists == 'true' }}
+          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 }}
-
-  unit:
-    needs: prepare-unit
-    if: ${{ needs.prepare-unit.outputs.matrix != '' }}
-    name: Unit
-    strategy:
-      fail-fast: false
-      matrix: ${{ fromJson(needs.prepare-unit.outputs.matrix) }}
-    uses: ./.github/workflows/reusable-unit.yml
-    secrets: inherit
-    with:
-      php: ${{ matrix.php }}
-      coverage: ${{ matrix.coverage == true }}
-      os: ${{ matrix.os || '' }}
-
-  prepare-functional:
-    name: Prepare matrix for functional tests
-    needs: get-matrix
-    runs-on: ubuntu-22.04
-    outputs:
-      matrix: ${{ steps.set-matrix.outputs.matrix }}
-    steps:
-      - name: Check out source code
-        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
-        with:
-          persist-credentials: false
-
-      - name: Check existence of composer.json & behat.yml files
-        id: check_files
-        run: echo "files_exists=$([ -f composer.json ] && [ -f behat.yml ] && echo true || echo false)" >> "$GITHUB_OUTPUT"
-
-      - name: Set matrix
-        id: set-matrix
+          WITH_COVERAGE: ${{ inputs.with-coverage }}
         run: |
-          if [[ $FILE_EXISTS == 'true' ]]; then
+          if [[ $FILE_EXISTS == 'true' && $DOCS_ONLY != 'true' ]]; then
             echo "matrix=$(jq -c \
-              --argjson with_coverage_flag "${{ inputs.with-coverage }}" \
+              --argjson with_coverage_flag "${WITH_COVERAGE}" \
               --arg minimum_php "${INPUTS_MINIMUM_PHP}" \
               --arg minimum_wp "${INPUTS_MINIMUM_WP}" \
               '
@@ -452,23 +505,36 @@ jobs:
                   ).wp |= $minimum_wp
                 )
               )
-              ' <<< "$BASE_MATRIX" )" >> $GITHUB_OUTPUT
+              ' <<< "$BASE_MATRIX" )" >> "$GITHUB_OUTPUT"
           else
-            echo "matrix=" >> $GITHUB_OUTPUT
+            echo "matrix=" >> "$GITHUB_OUTPUT"
           fi
-        env:
-          BASE_MATRIX: ${{ needs.get-matrix.outputs.matrix }}
-          FILE_EXISTS: ${{ steps.check_files.outputs.files_exists == 'true' }}
-          INPUTS_MINIMUM_PHP: ${{ inputs.minimum-php }}
-          INPUTS_MINIMUM_WP: ${{ inputs.minimum-wp }}
+
+  unit:
+    needs: prepare
+    if: ${{ needs.prepare.outputs.unit != '' }}
+    # The calling job's name is what the run view groups by, so it carries the
+    # grouping key. The called workflow names the individual leg within the group.
+    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 || '' }}
 
   functional:
-    needs: prepare-functional
-    if: ${{ needs.prepare-functional.outputs.matrix != '' }}
-    name: Behat
+    needs: prepare
+    if: ${{ needs.prepare.outputs.functional != '' }}
+    # Groups the Behat legs by PHP version, so the run view shows one collapsible
+    # entry per version instead of a single flat list of 41 jobs.
+    name: Behat | PHP ${{ matrix.php }}
     strategy:
       fail-fast: false
-      matrix: ${{ fromJson(needs.prepare-functional.outputs.matrix) }}
+      matrix: ${{ fromJson(needs.prepare.outputs.functional) }}
     uses: ./.github/workflows/reusable-functional.yml
     secrets: inherit
     with:
diff --git a/.github/workflows/reusable-unit.yml b/.github/workflows/reusable-unit.yml
index 03a183f..544bc54 100644
--- a/.github/workflows/reusable-unit.yml
+++ b/.github/workflows/reusable-unit.yml
@@ -10,24 +10,32 @@ on:
         required: false
         default: false
       os:
+        description: 'Runner to use. Defaults to ubuntu-22.04, or the RUNNERS_NAME repository variable when set.'
         type: string
         required: false
-        default: 'ubuntu-22.04'
+        default: ''
 
 permissions:
   contents: read
 
 jobs:
   unit:
-    name: Unit | PHP ${{ inputs.php }}${{ inputs.coverage && ' (with coverage)' || '' }}${{ startsWith( inputs.os, 'windows' ) && ' (Windows)' || '' }}${{ startsWith( inputs.os, 'macos' ) && ' (macOS)' || '' }}
-    runs-on: ${{ inputs.os || 'ubuntu-22.04' }}
+    # The calling job already states "Unit | PHP x" and groups on it, so this only
+    # needs to identify the leg within that group.
+    name: PHPUnit${{ 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-22.04' }}
     continue-on-error: ${{ inputs.php == 'nightly' }}
+    timeout-minutes: ${{ inputs.coverage && 30 || 15 }}
 
     steps:
       - name: Check out source code
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
+          show-progress: ${{ runner.debug == '1' && 'true' || 'false' }}
 
       - name: Set up PHP environment
         uses: shivammathur/setup-php@f3e473d116dcccaddc5834248c87452386958240 # v2
@@ -40,8 +48,20 @@ jobs:
         env:
           COMPOSER_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
+      # 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.
+      # Rotating the suffix weekly stops `dev-*` requirements from being served out
+      # of an indefinitely stale cache. `%Y-%W` is portable across the GNU, BSD and
+      # Git-for-Windows implementations of `date`.
+      - name: Determine the weekly Composer cache suffix
+        id: composer-cache-suffix
+        shell: bash
+        run: echo "value=$(date -u +%Y-%W)" >> "$GITHUB_OUTPUT"
+
       - name: Install Composer dependencies & cache dependencies
         uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
+        with:
+          custom-cache-suffix: ${{ steps.composer-cache-suffix.outputs.value }}
         env:
           COMPOSER_ROOT_VERSION: dev-${{ github.event.repository.default_branch }}
 
diff --git a/.github/workflows/sync-workflows.yml b/.github/workflows/sync-workflows.yml
index 6491a4a..fab9d94 100644
--- a/.github/workflows/sync-workflows.yml
+++ b/.github/workflows/sync-workflows.yml
@@ -6,17 +6,40 @@ on:
     branches:
       - main
       - master
+    paths:
+      - '.actrc'
+      - '.editorconfig'
+      - 'AGENTS.md'
+      - '.github/dependabot.yml'
+      - '.github/workflows/check-branch-alias.yml'
+      - '.github/workflows/copilot-setup-steps.yml'
+      - '.github/workflows/issue-triage.yml'
+      - '.github/workflows/manage-labels.yml'
+      - '.github/workflows/regenerate-readme.yml'
+      - '.github/workflows/welcome-new-contributors.yml'
+      - '.github/workflows/sync-workflows.yml'
   schedule:
-    - cron:  '*/10 * * * *' # Run every 10 minutes.
+    - cron:  '43 4 * * *' # Daily, to catch drift from out-of-band edits.
 
 permissions:
   contents: read
 
+# A sync pushes to every target repository, so only one may be in flight at a
+# time. Queued runs wait instead of cancelling, so a sync that has already
+# started always gets to finish.
+concurrency:
+  group: ${{ github.workflow }}
+  cancel-in-progress: false
+
 jobs:
 
   sync-workflows:
     name: Sync GitHub Actions workflows
     runs-on: ubuntu-latest
+    # Generous, because the job pushes to ~45 repositories. It exists to bound a
+    # pathological run, not to pace a healthy one. The sync is idempotent, so a
+    # run cut short here is completed by the next push or the daily schedule.
+    timeout-minutes: 60
     if: ${{ github.repository_owner == 'wp-cli' }}
     permissions:
       contents: write
@@ -84,6 +107,10 @@ jobs:
   sync-dependabot:
     name: Sync Dependabot configuration
     runs-on: ubuntu-latest
+    # Generous, because the job pushes to ~45 repositories. It exists to bound a
+    # pathological run, not to pace a healthy one. The sync is idempotent, so a
+    # run cut short here is completed by the next push or the daily schedule.
+    timeout-minutes: 60
     if: ${{ github.repository_owner == 'wp-cli' }}
     permissions:
       contents: write