diff --git a/dev-vcs/tortoisehg/tortoisehg-4.0.ebuild b/dev-vcs/tortoisehg/tortoisehg-4.0.ebuild
index 811a0e69f6090..c5d115921ab2d 100644
--- a/dev-vcs/tortoisehg/tortoisehg-4.0.ebuild
+++ b/dev-vcs/tortoisehg/tortoisehg-4.0.ebuild
@@ -69,6 +69,10 @@ python_install_all() {
 	fi
 	newicon -s scalable icons/scalable/apps/thg.svg thg_logo.svg
 	domenu contrib/thg.desktop
+
+	# Remove file that collides with >=mercurial-4.0 (bug #599266).
+	rm "${ED}"/usr/$(get_libdir)/${EPYTHON}/site-packages/hgext3rd/__init__.py \
+		|| die
 }
 
 pkg_postinst() {