diff --git a/README.md b/README.md
index 1c52a51..47beeb4 100644
--- a/README.md
+++ b/README.md
@@ -602,6 +602,7 @@ Grouped in options:\
 [DealStreetAsia](https://www.dealstreetasia.com) -
 [Harvard Business Review China](https://www.hbrchina.org) -
 [Harvard Business Review Taiwan](https://www.hbrtaiwan.com) -
+[Mainichi Shimbun](https://mainichi.jp) -
 [Nikkei Asian Review](https://asia.nikkei.com) -
 [NK News](https://www.nknews.org)* -
 [South China Morning Post](https://www.scmp.com) -
diff --git a/changelog.txt b/changelog.txt
index 4cb2cae..ce47f79 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -2,6 +2,7 @@
 Changelog Bypass Paywalls Clean - Firefox
 
 Post-release
+Add Mainichi Shimbun (Japan)
 
 * v2.5.1.0 (2022-01-09)
 Add group Hearst Communications (local USA)
diff --git a/manifest.json b/manifest.json
index 75ad66c..f65457d 100644
--- a/manifest.json
+++ b/manifest.json
@@ -340,6 +340,7 @@
         "*://*.lrb.co.uk/*",
         "*://*.lunion.fr/*",
         "*://*.lvz.de/*",
+        "*://*.mainichi.jp/*",
         "*://*.marca.com/*",
         "*://*.marianne.net/*",
         "*://*.marketwatch.com/*",
@@ -606,5 +607,5 @@
         "*://*.wsj.net/*",
         "*://*.zephr.com/*"
     ],
-    "version": "2.5.1.0"
+    "version": "2.5.1.1"
 }
diff --git a/options/options.js b/options/options.js
index a9b50ae..3fb8abe 100644
--- a/options/options.js
+++ b/options/options.js
@@ -141,7 +141,7 @@ function selectNone() {
 }
 
 function closeButton() {
-  open(location).close();
+  window.close();
 }
 
 function check_sites_updated() {
diff --git a/sites.js b/sites.js
index d60ef5c..3e3f5f7 100644
--- a/sites.js
+++ b/sites.js
@@ -985,6 +985,11 @@ var defaultSites = {
     allow_cookies: 1,
     block_regex: /cdn\.ampproject\.org\/v\d\/amp-(ad|subscriptions)-.+\.js/
   },
+  "Mainichi Shimbun": {
+    domain: "mainichi.jp",
+    allow_cookies: 1,
+    useragent: "googlebot"
+  },
   "Marca": {
     domain: "marca.com",
     group_rule: "###_gr_es_unidad_domains"
diff --git a/sites_updated.json b/sites_updated.json
index 6f7241d..0cc2c1e 100644
--- a/sites_updated.json
+++ b/sites_updated.json
@@ -24,6 +24,11 @@
     "amp_unhide": 1,
     "block_regex": "cdn\\.ampproject\\.org\\/v\\d\\/amp-((sticky-)?ad|subscriptions)-.+\\.js"
   },
+  "Mainichi Shimbun": {
+    "domain": "mainichi.jp",
+    "allow_cookies": 1,
+    "useragent": "googlebot"
+  },
   "Science (free articles only)": {
     "domain": "science.org",
     "allow_cookies": 1,