diff --git a/graylog2-web-interface/webpack.config.js b/graylog2-web-interface/webpack.config.js
index <HASH>..<HASH> 100644
--- a/graylog2-web-interface/webpack.config.js
+++ b/graylog2-web-interface/webpack.config.js
@@ -160,6 +160,10 @@ if (TARGET === 'build') {
           minimize: true,
           sourceMap: true,
           compress: {
+            // Conditionals compression caused issue #5450 so they should be disabled for now.
+            // Looking at uglify-js issues, it seems that the latest changes in version 3.4.9 broke conditionals
+            // compression. For example: https://github.com/mishoo/UglifyJS2/issues/3269
+            conditionals: false,
             warnings: false,
           },
           mangle: {
Fix assets compression on production builds (#<I>)

Due to a bug in uglify-js <I>, compressing conditionals during asset

minimization is broken, leading to #<I>.



This commit disables conditionals compression until we can test it is fixed

in a future uglify-js release.



There are several reports in the upstream project, one of them is:

<URL>