diff --git a/README.md b/README.md
index e0b8c63..401e80a 100644
--- a/README.md
+++ b/README.md
@@ -52,6 +52,7 @@ Currently, ChromeXt supports almost all [Tampermonkey APIs](https://www.tampermo
 5. @grant: GM_addStyle, GM_addElement, GM_xmlhttpRequest, GM_openInTab, GM_registerMenuCommand (shown in the `Resources` panel of eruda), GM_unregisterMenuCommand, GM_download, unsafeWindow (= window)
 6. @grant: GM_setValue, GM_getValue (less powerful than GM.getValue), GM_listValues, GM_addValueChangeListener, GM_removeValueChangeListener, GM_setClipboard, GM_cookie, GM_notification
 7. @require, @resource (without [Subresource Integrity](https://www.tampermonkey.net/documentation.php#api:Subresource_Integrity))
+8. window.close (implemented for most Chromium based browsers)
 
 These APIs are implemented differently from the official ones, please refer to the source files
 [Local.kt](app/src/main/java/org/matrix/chromext/script/Local.kt) and
diff --git a/app/src/main/assets/GM.js b/app/src/main/assets/GM.js
index 2801af0..b0af3cb 100644
--- a/app/src/main/assets/GM.js
+++ b/app/src/main/assets/GM.js
@@ -1078,12 +1078,12 @@ GM.bootstrap = () => {
 
   const grants = meta.grants;
 
-  if (
-    meta["inject-into"] == "page" ||
-    grants.includes("none") ||
-    grants.includes("unsafeWindow")
-  ) {
+  if (meta["inject-into"] == "page" || grants.includes("none")) {
     GM.globalThis = window;
+    if (grants.includes("window.close")) {
+      // The page may abuse window.close
+      window.close = () => ChromeXt.dispatch("close");
+    }
   } else {
     const handler = {
       // A handler to block access to globalThis
@@ -1108,7 +1108,9 @@ GM.bootstrap = () => {
       get(target, prop, receiver) {
         if (target[prop] == target) return receiver;
         // Block possible jail break
-        if (this.keys.includes(prop)) {
+        if (prop == "close" && grants.includes("window.close")) {
+          return () => ChromeXt.dispatch("close");
+        } else if (this.keys.includes(prop)) {
           const val = target[prop];
           return typeof val == "function" ? val.bind(target) : val;
         } else if (
diff --git a/app/src/main/java/org/matrix/chromext/Listener.kt b/app/src/main/java/org/matrix/chromext/Listener.kt
index 5790adc..d57ccc7 100644
--- a/app/src/main/java/org/matrix/chromext/Listener.kt
+++ b/app/src/main/java/org/matrix/chromext/Listener.kt
@@ -36,7 +36,9 @@ import org.matrix.chromext.script.parseScript
 import org.matrix.chromext.utils.ERUD_URL
 import org.matrix.chromext.utils.Log
 import org.matrix.chromext.utils.XMLHttpRequest
+import org.matrix.chromext.utils.findMethod
 import org.matrix.chromext.utils.invalidUserScriptUrls
+import org.matrix.chromext.utils.invokeMethod
 import org.matrix.chromext.utils.isChromeXtFrontEnd
 import org.matrix.chromext.utils.isDevToolsFrontEnd
 import org.matrix.chromext.utils.isUserScript
@@ -143,6 +145,45 @@ object Listener {
         if (isUserScript(url)) invalidUserScriptUrls.add(url!!)
         callback = "if (Symbol.ChromeXt) Symbol.ChromeXt.lock(${Local.key},'${Local.name}');"
       }
+      "close" -> {
+        val activity = Chrome.getContext()
+        if (Chrome.isSamsung &&
+            currentTab != null &&
+            activity::class.java ==
+                Chrome.load("com.sec.android.app.sbrowser.SBrowserMainActivity")) {
+          val manager = activity.invokeMethod { name == "getTabManager" }!!
+          @Suppress("UNCHECKED_CAST")
+          val tabList = manager.invokeMethod { name == "getAllTabList" } as List<Any>
+          tabList
+              .find { it.invokeMethod { name == "getTab" } == currentTab }
+              ?.also { manager.invokeMethod(it) { name == "closeTab" } }
+        } else if (currentTab != null &&
+            activity::class.java == UserScriptProxy.chromeTabbedActivity) {
+          val tab = Chrome.load("org.chromium.chrome.browser.tab.Tab")
+          val tabModel = Chrome.load("org.chromium.chrome.browser.tabmodel.TabModel")
+          val getCurrentTabModel =
+              findMethod(activity::class.java, true) {
+                parameterTypes.size == 0 && returnType == tabModel
+              }
+          val model = getCurrentTabModel.invoke(activity)!!
+          val closeTab =
+              findMethod(model::class.java) {
+                returnType == Boolean::class.java &&
+                    parameterTypes contentDeepEquals
+                        arrayOf(
+                            tab,
+                            tab,
+                            Boolean::class.java,
+                            Boolean::class.java,
+                            Boolean::class.java,
+                            Int::class.java)
+              }
+          closeTab.invoke(model, currentTab, null, false, false, false, 0)
+        } else {
+          val msg = "Closing tab ${currentTab} with context ${activity}"
+          callback = "console.error(new TypeError('ChromeXt Action failure', {cause: '${msg}'}));"
+        }
+      }
       "focus" -> {
         Chrome.updateTab(currentTab)
       }
diff --git a/app/src/main/java/org/matrix/chromext/MainHook.kt b/app/src/main/java/org/matrix/chromext/MainHook.kt
index 9fad9bd..09c25ae 100644
--- a/app/src/main/java/org/matrix/chromext/MainHook.kt
+++ b/app/src/main/java/org/matrix/chromext/MainHook.kt
@@ -65,7 +65,7 @@ class MainHook : IXposedHookLoadPackage, IXposedHookZygoteInit {
                 }
                 .onFailure {
                   initHooks(ContextMenuHook)
-                  if (BuildConfig.DEBUG) Log.ex(it)
+                  if (BuildConfig.DEBUG && !Chrome.isSamsung) Log.ex(it)
                 }
           }
     } else {
diff --git a/app/src/main/java/org/matrix/chromext/script/Local.kt b/app/src/main/java/org/matrix/chromext/script/Local.kt
index 3cb678d..2b4b76d 100644
--- a/app/src/main/java/org/matrix/chromext/script/Local.kt
+++ b/app/src/main/java/org/matrix/chromext/script/Local.kt
@@ -49,6 +49,7 @@ object GM {
         "none" -> return@forEach
         "GM_info" -> return@forEach
         "GM.ChromeXt" -> return@forEach
+        "window.close" -> return@forEach
         else ->
             if (localScript.containsKey(it)) {
               grants += localScript.get(it)