https://github.com/pytest-dev/pytest-forked/issues/84

--- pytest-forked-1.6.0/tox.ini.orig
+++ pytest-forked-1.6.0/tox.ini
@@ -19,7 +19,6 @@
   pytest62: pytest~=6.2
   pytestlatest: pytest
   pytestmain: git+https://github.com/pytest-dev/pytest.git@main
-platform=linux|darwin
 commands=
   pytest {posargs}