From 28ff1ed7b6331fe89995c1e82ecd93bc479eadb5 Mon Sep 17 00:00:00 2001
From: Artur Signell <artur@vaadin.com>
Date: Wed, 24 Feb 2021 11:09:43 +0200
Subject: [PATCH] Keep existing style sheets in document when adding own

Fixes https://github.com/brave/brave-browser/issues/14333
---
 .../renderer/cosmetic_filters_js_handler.cc               | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/components/cosmetic_filters/renderer/cosmetic_filters_js_handler.cc b/components/cosmetic_filters/renderer/cosmetic_filters_js_handler.cc
index 13113cd7481f..e792a6eac628 100644
--- a/components/cosmetic_filters/renderer/cosmetic_filters_js_handler.cc
+++ b/components/cosmetic_filters/renderer/cosmetic_filters_js_handler.cc
@@ -68,7 +68,7 @@ const char kHideSelectorsInjectScript[] =
           if (!document.adoptedStyleSheets.includes(
               window.content_cosmetic.cosmeticStyleSheet)) {
             document.adoptedStyleSheets =
-              [window.content_cosmetic.cosmeticStyleSheet];
+              [...document.adoptedStyleSheets, window.content_cosmetic.cosmeticStyleSheet];
           };
         })();)";
 
@@ -92,7 +92,7 @@ const char kForceHideSelectorsInjectScript[] =
           if (!document.adoptedStyleSheets.includes(
               window.content_cosmetic.cosmeticStyleSheet)) {
             document.adoptedStyleSheets =
-              [window.content_cosmetic.cosmeticStyleSheet];
+              [...document.adoptedStyleSheets, window.content_cosmetic.cosmeticStyleSheet];
           };
         })();)";
 
@@ -123,8 +123,8 @@ const char kStyleSelectorsInjectScript[] =
           };
           if (!document.adoptedStyleSheets.includes(
                 window.content_cosmetic.cosmeticStyleSheet)){
-             document.adoptedStyleSheets =
-               [window.content_cosmetic.cosmeticStyleSheet];
+              document.adoptedStyleSheets =
+                [...document.adoptedStyleSheets, window.content_cosmetic.cosmeticStyleSheet];
           };
         })();)";