diff --git a/src/octoprint/plugins/pluginmanager/__init__.py b/src/octoprint/plugins/pluginmanager/__init__.py
index 35f38447..a6806ac7 100644
--- a/src/octoprint/plugins/pluginmanager/__init__.py
+++ b/src/octoprint/plugins/pluginmanager/__init__.py
@@ -306,7 +306,7 @@ class PluginManagerPlugin(octoprint.plugin.SimpleApiPlugin,
 
 	def command_install(self, url=None, path=None, force=False, reinstall=None, dependency_links=False):
 		if url is not None:
-			if not any(map(lambda scheme: url.starts_with(scheme + "://"), self.URL_SCHEMES)):
+			if not any(map(lambda scheme: url.startswith(scheme + "://"), self.URL_SCHEMES)):
 				raise ValueError("Invalid URL to pip install from")
 			
 			source = url