From c008443f2d668f270415f907f1818f458814d646 Mon Sep 17 00:00:00 2001
From: Daniel Waterworth <me@danielwaterworth.com>
Date: Tue, 5 Nov 2019 11:24:52 +0000
Subject: [PATCH] FIX: filterQueryParams mutates state that is essentially
 global

Let's prevent it from doing this by duplicating the input first.
---
 .../javascripts/discourse/routes/build-topic-route.js.es6      | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/app/assets/javascripts/discourse/routes/build-topic-route.js.es6 b/app/assets/javascripts/discourse/routes/build-topic-route.js.es6
index e892876dfe3..fb4249205d0 100644
--- a/app/assets/javascripts/discourse/routes/build-topic-route.js.es6
+++ b/app/assets/javascripts/discourse/routes/build-topic-route.js.es6
@@ -4,7 +4,8 @@ import { defaultHomepage } from "discourse/lib/utilities";
 
 // A helper to build a topic route for a filter
 function filterQueryParams(params, defaultParams) {
-  const findOpts = defaultParams || {};
+  const findOpts = Object.assign({}, defaultParams || {});
+
   if (params) {
     Object.keys(queryParams).forEach(function(opt) {
       if (params[opt]) {