diff --git a/webextensions-emulator-master/yarn.lock b/webextensions-emulator-master/yarn.lock
index 1d64e68..6193369 100644
--- a/webextensions-emulator-master/yarn.lock
+++ b/webextensions-emulator-master/yarn.lock
@@ -657,9 +657,9 @@ browserify-zlib@^0.2.0:
     pako "~1.0.5"
 
 buffer-from@^1.0.0:
-  version "1.1.1"
-  resolved "https://registry.npm.taobao.org/buffer-from/download/buffer-from-1.1.1.tgz#32713bc028f75c02fdb710d7c7bcec1f2c6070ef"
-  integrity sha1-MnE7wCj3XAL9txDXx7zsHyxgcO8=
+  version "1.1.2"
+  resolved "https://registry.yarnpkg.com/buffer-from/-/buffer-from-1.1.2.tgz#2b146a6fd72e80b4f55d255f35ed59a3a9a41bd5"
+  integrity sha512-E+XQCRwSbaaiChtv6k6Dwgc+bx+Bs6vuKJHHl5kox/BaKbhiXzqQOwK4cO22yElGp2OCmjwVhT3HmxgyPGnJfQ==
 
 buffer-indexof@^1.0.0:
   version "1.1.1"
@@ -910,8 +910,8 @@ commander@2.17.x:
 
 commander@^2.20.0:
   version "2.20.3"
-  resolved "https://registry.npm.taobao.org/commander/download/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
-  integrity sha1-/UhehMA+tIgcIHIrpIA16FMa6zM=
+  resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
+  integrity sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==
 
 commander@~2.19.0:
   version "2.19.0"
@@ -4423,9 +4423,9 @@ source-map-resolve@^0.5.0:
     urix "^0.1.0"
 
 source-map-support@~0.5.12:
-  version "0.5.16"
-  resolved "https://registry.npm.taobao.org/source-map-support/download/source-map-support-0.5.16.tgz?cache=0&sync_timestamp=1572390065703&other_urls=https%3A%2F%2Fregistry.npm.taobao.org%2Fsource-map-support%2Fdownload%2Fsource-map-support-0.5.16.tgz#0ae069e7fe3ba7538c64c98515e35339eac5a042"
-  integrity sha1-CuBp5/47p1OMZMmFFeNTOerFoEI=
+  version "0.5.21"
+  resolved "https://registry.yarnpkg.com/source-map-support/-/source-map-support-0.5.21.tgz#04fe7c7f9e1ed2d662233c28cb2b35b9f63f6e4f"
+  integrity sha512-uBHU3L3czsIyYXKX88fdrGovxdSCoTGDRZ6SYXtSRxLZUzHg5P/66Ht6uoUlHu9EZod+inXhKo3qQgwXUT/y1w==
   dependencies:
     buffer-from "^1.0.0"
     source-map "^0.6.0"
@@ -4726,9 +4726,9 @@ terser-webpack-plugin@^1.4.3:
     worker-farm "^1.7.0"
 
 terser@^4.1.2:
-  version "4.6.3"
-  resolved "https://registry.npm.taobao.org/terser/download/terser-4.6.3.tgz#e33aa42461ced5238d352d2df2a67f21921f8d87"
-  integrity sha1-4zqkJGHO1SONNS0t8qZ/IZIfjYc=
+  version "4.8.1"
+  resolved "https://registry.yarnpkg.com/terser/-/terser-4.8.1.tgz#a00e5634562de2239fd404c649051bf6fc21144f"
+  integrity sha512-4GnLC0x667eJG0ewJTa6z/yXrbLGv80D9Ru6HIpCQmO+Q4PfEtBFi0ObSckqwL6VyQv/7ENJieXHo2ANmdQwgw==
   dependencies:
     commander "^2.20.0"
     source-map "~0.6.1"