diff --git a/pyproject.toml b/pyproject.toml
index d0c0ecf09..53a1221fa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -359,6 +359,7 @@ markers = [
     "requires_internet: marks tests that need real Internet access",
 ]
 filterwarnings = [
+    # Envs with pinned old dependencies opt out of this, see tox.ini.
     "error",
     "ignore::DeprecationWarning:twisted.web.static",
     # Twisted leaves the listening socket open after a failed bind
@@ -372,12 +373,8 @@ filterwarnings = [
     # queuelib's test helpers (reused by tests/test_squeues.py) leave queue
     # files open; the resulting warning surfaces at an arbitrary GC point.
     "ignore:.*<_io\\.FileIO name=.*queuelib-tests-:pytest.PytestUnraisableExceptionWarning",
-    # pyftpdlib imports the deprecated asyncore/asynchat modules on Python < 3.12.
-    "ignore:The async(ore|hat) module is deprecated:DeprecationWarning",
-    # Old w3lib (min env) compiles a regex with inline flags not at the start.
-    "ignore:Flags not at the start of the expression:DeprecationWarning",
-    # Old Twisted (min env) calls the deprecated threading.currentThread().
-    "ignore:currentThread\\(\\) is deprecated:DeprecationWarning",
+    # itemadapter imports pydantic.v1, which warns on Python 3.14 and higher.
+    "ignore:Core Pydantic V1 functionality isn't compatible:UserWarning",
 ]
 
 [tool.ruff.lint]
diff --git a/tests/ignores.txt b/tests/ignores.txt
index 3717bbc95..5be8576f3 100644
--- a/tests/ignores.txt
+++ b/tests/ignores.txt
@@ -1,3 +1,4 @@
 scrapy/core/downloader/handlers/http.py
 scrapy/extensions/statsmailer.py
+scrapy/interfaces.py
 scrapy/mail.py
diff --git a/tests/test_command_shell.py b/tests/test_command_shell.py
index 5f8ad5a35..501f7132e 100644
--- a/tests/test_command_shell.py
+++ b/tests/test_command_shell.py
@@ -162,6 +162,16 @@ class TestShellCommand:
         assert ret == 0, out
 
 
+def _stop(p: PopenSpawn[str]) -> None:
+    p.sendeof()
+    p.wait()  # type: ignore[no-untyped-call]
+    # PopenSpawn leaves the subprocess pipes open, which triggers
+    # ResourceWarning at an arbitrary garbage collection point.
+    for pipe in (p.proc.stdin, p.proc.stdout):
+        if pipe:
+            pipe.close()
+
+
 class TestInteractiveShell:
     def test_fetch(self, mockserver: MockServer) -> None:
         args = (
@@ -179,12 +189,7 @@ class TestInteractiveShell:
         p.sendline(f"fetch('{mockserver.url('/')}')")
         p.sendline("type(response)")
         p.expect_exact("HtmlResponse")
-        p.sendeof()
-        p.wait()  # type: ignore[no-untyped-call]
-        if p.proc.stdin:
-            p.proc.stdin.close()
-        if p.proc.stdout:
-            p.proc.stdout.close()
+        _stop(p)
         logfile.seek(0)
         assert "Traceback" not in logfile.read().decode()
 
@@ -210,12 +215,7 @@ class TestInteractiveShell:
         p = PopenSpawn(args, env=env, timeout=5)
         p.logfile_read = logfile
         p.expect_exact("Available Scrapy objects")
-        p.sendeof()
-        p.wait()  # type: ignore[no-untyped-call]
-        if p.proc.stdin:
-            p.proc.stdin.close()
-        if p.proc.stdout:
-            p.proc.stdout.close()
+        _stop(p)
         logfile.seek(0)
         return logfile.read().decode()
 
@@ -240,12 +240,7 @@ class TestInteractiveShell:
         # shell=python was honored, regardless of platform-specific prompts.
         p.sendline("import sys; print('IPYMODULE', 'IPython' in sys.modules)")
         p.expect_exact("IPYMODULE False")
-        p.sendeof()
-        p.wait()  # type: ignore[no-untyped-call]
-        if p.proc.stdin:
-            p.proc.stdin.close()
-        if p.proc.stdout:
-            p.proc.stdout.close()
+        _stop(p)
         logfile.seek(0)
         assert "Traceback" not in logfile.read().decode()
 
diff --git a/tox.ini b/tox.ini
index e10a7cc0c..b63295518 100644
--- a/tox.ini
+++ b/tox.ini
@@ -147,6 +147,9 @@ deps =
     {[test-requirements]deps}
 setenv =
     _SCRAPY_MIN=true
+    # Pinned old Python and library versions trigger warnings that we cannot
+    # fix, so these envs do not turn warnings into errors.
+    PYTEST_ADDOPTS=-W default {env:PYTEST_ADDOPTS:}
 commands =
     pytest {posargs:--cov-config=pyproject.toml --cov=scrapy --cov-report=xml --cov-report= --junitxml=min.junit.xml -o junit_family=legacy --durations=10 scrapy tests}