diff --git a/src/node/utils/caching_middleware.js b/src/node/utils/caching_middleware.js
index 6df4faa97..f03e5aa4b 100644
--- a/src/node/utils/caching_middleware.js
+++ b/src/node/utils/caching_middleware.js
@@ -21,6 +21,7 @@ var path = require('path');
 var zlib = require('zlib');
 var settings = require('./Settings');
 var existsSync = require('./path_exists');
+const url = require('url');
 
 /*
  * The crypto module can be absent on reduced node installations.
@@ -91,8 +92,14 @@ CachingMiddleware.prototype = new function () {
     var supportsGzip =
         (req.get('Accept-Encoding') || '').indexOf('gzip') != -1;
 
-    var path = require('url').parse(req.url).path;
-    var cacheKey = generateCacheKey(path);
+    /**
+     * `req.url` is either /file?callback=require.define&v=versionString
+     * or /file.
+     *
+     * invalid.invalid is just a placeholder
+     */
+    let path = new url.URL(req.url, 'http://invalid.invalid').pathname;
+    let cacheKey = generateCacheKey(path);
 
     fs.stat(CACHE_DIR + 'minified_' + cacheKey, function (error, stats) {
       var modifiedSince = (req.headers['if-modified-since']
diff --git a/tests/backend/specs/caching_middleware.js b/tests/backend/specs/caching_middleware.js
index a8ff2b615..c7946e8bc 100644
--- a/tests/backend/specs/caching_middleware.js
+++ b/tests/backend/specs/caching_middleware.js
@@ -9,6 +9,8 @@ const settings = require('../../../src/node/utils/Settings');
 const assert = require('assert').strict;
 const url = require('url');
 const queryString = require('querystring');
+const fs = require('fs');
+const path = require('path');
 
 let agent;
 
@@ -165,4 +167,20 @@ describe(__filename, function() {
     })
   });
 
+  context("different callback or version parameter", function(){
+    it('should never create new files', async function(){
+      const pathToVar = path.join(__filename, '../../../../var');
+
+      // the number of files in ./var should not change during this test
+      const minifiedFilesBefore = (await fs.promises.readdir(pathToVar)).length;
+      const resource1 = "/javascripts/lib/ep_etherpad-lite/static/js/ace2_common.js?callback=require.define";
+      const resource2 = "/javascripts/lib/ep_etherpad-lite/static/js/ace2_common.js?callback=require";
+      const resource3 = "/javascripts/lib/ep_etherpad-lite/static/js/ace2_common.js?callback=require.define&v=1234";
+      await agent.get(resource1);
+      await agent.get(resource2);
+      await agent.get(resource3);
+      const minifiedFilesAfter = (await fs.promises.readdir(pathToVar)).length;
+      assert.equal(minifiedFilesBefore, minifiedFilesAfter);
+    })
+  })
 });