diff --git a/index.js b/index.js
index 923d1b6..1b67ce2 100644
--- a/index.js
+++ b/index.js
@@ -39,7 +39,6 @@ function random_string (len = 8) {
     throw new Error ('invalid length');
   return crypto.randomBytes (Math.ceil (len * 3 / 4))
     .toString ('base64')
-    .replace (/[=]+$/u, '')
     .substr (0, len);
 }
 
diff --git a/stryker.conf.js b/stryker.conf.js
index 86e8ef8..924c3bb 100644
--- a/stryker.conf.js
+++ b/stryker.conf.js
@@ -2,7 +2,7 @@ module.exports = function(config) {
   config.set({
     mutator: "javascript",
     packageManager: "yarn",
-    reporters: ["clear-text"],
+    reporters: ["clear-text", "progress"],
     testRunner: "command",
     transpilers: [],
     coverageAnalysis: "all",