diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 7ff27643f10..3c8bf58d2d9 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -881,6 +881,8 @@ def _get_plugin_specs_as_list(
     if isinstance(specs, str):
         return specs.split(",") if specs else []
     # Direct specification.
+    if type(specs) is list or type(specs) is tuple:
+        return list(specs)
     if isinstance(specs, collections.abc.Sequence):
         return list(specs)
     raise UsageError(
@@ -1484,9 +1486,9 @@ def _get_unknown_ini_keys(self) -> List[str]:
 
     def parse(self, args: List[str], addopts: bool = True) -> None:
         # Parse given cmdline arguments into this config object.
-        assert (
-            self.args == []
-        ), "can only parse cmdline args at most once per Config object"
+        assert self.args == [], (
+            "can only parse cmdline args at most once per Config object"
+        )
         self.hook.pytest_addhooks.call_historic(
             kwargs=dict(pluginmanager=self.pluginmanager)
         )
@@ -1906,7 +1908,7 @@ def parse_warning_filter(
         parts.append("")
     action_, message, category_, module, lineno_ = (s.strip() for s in parts)
     try:
-        action: "warnings._ActionKind" = warnings._getaction(action_)  # type: ignore[attr-defined]
+        action: warnings._ActionKind = warnings._getaction(action_)  # type: ignore[attr-defined]
     except warnings._OptionError as e:
         raise UsageError(error_template.format(error=str(e))) from None
     try: