diff --git a/.github/workflows/tox.yml b/.github/workflows/tox.yml
index b531cbd..13db395 100644
--- a/.github/workflows/tox.yml
+++ b/.github/workflows/tox.yml
@@ -31,7 +31,7 @@ jobs:
     steps:
       - name: Determine matrix
         id: generate_matrix
-        uses: coactions/dynamic-matrix@v4
+        uses: ansible/actions/matrix@v1
         with:
           min_python: "3.10"
           max_python: "3.14"
@@ -95,9 +95,9 @@ jobs:
         if: ${{ matrix.command5 }}
 
       - name: Archive logs
-        uses: coactions/upload-artifact@v4
+        uses: actions/upload-artifact@v4
         with:
-          name: logs-${{ matrix.name }}.zip
+          name: logs-${{ matrix.name }}
           include-hidden-files: true
           if-no-files-found: ignore
           path: |
@@ -132,20 +132,12 @@ jobs:
 
       - run: pip3 install 'coverage>=7.5.1'
 
-      - name: Merge logs into a single archive
-        uses: actions/upload-artifact/merge@v4
-        with:
-          name: logs.zip
-          include-hidden-files: true
-          pattern: logs-*.zip
-          # artifacts like py312.zip and py312-macos do have overlapping files
-          separate-directories: true
-
       - name: Download artifacts
         uses: actions/download-artifact@v4
         continue-on-error: true # to allow rerunning this job
         with:
-          name: logs.zip
+          pattern: logs-*
+          merge-multiple: true
           path: .
 
 
@@ -154,7 +146,7 @@ jobs:
         with:
           name: ${{ matrix.name }}
           # verbose: true # optional (default = false)
-          fail_ci_if_error: true
+          fail_ci_if_error: false
           use_oidc: ${{ !(github.event_name == 'pull_request' && github.event.pull_request.head.repo.fork) }} # cspell:ignore oidc
 
       - name: Decide whether the needed jobs succeeded or failed
diff --git a/.gitignore b/.gitignore
index 28baac9..145029c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -57,3 +57,4 @@ src/doc8/_version.py
 .idea/
 .vscode/
 junit.xml
+uv.lock
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index a27605a..53f50e7 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -9,7 +9,7 @@ repos:
     - id: trailing-whitespace
     - id: check-executables-have-shebangs
   - repo: https://github.com/asottile/pyupgrade
-    rev: v3.20.0
+    rev: v3.21.2
     hooks:
       - id: pyupgrade
   - repo: https://github.com/pappasam/toml-sort
diff --git a/src/doc8/checks.py b/src/doc8/checks.py
index 2b6870f..77ac59f 100644
--- a/src/doc8/checks.py
+++ b/src/doc8/checks.py
@@ -121,6 +121,10 @@ class CheckValidity(ContentCheck):
         re.compile(
             r'^PEP number must be a number from 0 to 9999; "\d{1,4}#[^"]*" is invalid.',
         ),
+        re.compile(
+            r'^Error in "(?:admonition|attention|caution|danger|error|hint|important|note|tip|warning)" directive:\nunknown option: "collapsible"',
+            re.MULTILINE,
+        ),
     ]
 
     def __init__(self, cfg):
diff --git a/src/doc8/tests/test_checks.py b/src/doc8/tests/test_checks.py
index 155c1ff..b4a50cd 100644
--- a/src/doc8/tests/test_checks.py
+++ b/src/doc8/tests/test_checks.py
@@ -183,3 +183,26 @@ def test_newline(self):
                 check = checks.CheckNewlineEndOfFile({})
                 errors = list(check.report_iter(parsed_file))
                 self.assertEqual(expected_errors, len(errors))
+
+
+class TestValidity(unittest.TestCase):
+    def test_collapsible_admonition_ignored_in_sphinx_mode(self):
+        content = b".. note::\n   :collapsible:\n\n   Collapsible note.\n"
+        with tempfile.NamedTemporaryFile(suffix=".rst") as fh:
+            fh.write(content)
+            fh.flush()
+            parsed_file = parser.ParsedFile(fh.name)
+            check = checks.CheckValidity({"sphinx": True})
+            errors = list(check.report_iter(parsed_file))
+            self.assertEqual(0, len(errors))
+
+    def test_collapsible_admonition_flagged_without_sphinx_mode(self):
+        content = b".. note::\n   :collapsible:\n\n   Collapsible note.\n"
+        with tempfile.NamedTemporaryFile(suffix=".rst") as fh:
+            fh.write(content)
+            fh.flush()
+            parsed_file = parser.ParsedFile(fh.name)
+            check = checks.CheckValidity({"sphinx": False})
+            errors = list(check.report_iter(parsed_file))
+            self.assertEqual(1, len(errors))
+            self.assertEqual("D000", errors[0][1])