diff --git a/app/assets/javascripts/discourse/lib/plugin-api.js.es6 b/app/assets/javascripts/discourse/lib/plugin-api.js.es6
index 6fc005c5c65..8c045179656 100644
--- a/app/assets/javascripts/discourse/lib/plugin-api.js.es6
+++ b/app/assets/javascripts/discourse/lib/plugin-api.js.es6
@@ -321,30 +321,3 @@ function decorate(klass, evt, cb) {
 export function decorateCooked() {
   console.warn('`decorateCooked` has been removed. Use `getPluginApi(version).decorateCooked` instead');
 }
-
-// This is backported so plugins in the new format will not raise errors
-//
-// To upgrade your plugin for backwards compatibility, you can add code in this
-// form:
-//
-//   function newApiCode(api) {
-//     // api.xyz();
-//   }
-//
-//   function oldCode() {
-//     // your pre-PluginAPI code goes here. You will be able to delete this
-//     // code once the `PluginAPI` has been rolled out to all versions of
-//     // Discourse you want to support.
-//   }
-//
-//   // `newApiCode` will use API version 0.1, if no API support then
-//   // `oldCode` will be called
-//   withPluginApi('0.1', newApiCode, { noApi: oldCode });
-//
-export function withPluginApi(version, apiCodeCallback, opts) {
-  console.warn(`Plugin API v${version} is not supported`);
-
-  if (opts && opts.noApi) {
-    return opts.noApi();
-  }
-}