diff --git a/VimR/VimR.xcodeproj/project.pbxproj b/VimR/VimR.xcodeproj/project.pbxproj
index 771da462..1dad7134 100644
--- a/VimR/VimR.xcodeproj/project.pbxproj
+++ b/VimR/VimR.xcodeproj/project.pbxproj
@@ -35,6 +35,7 @@
 		1929B542A071BD03C846F6EF /* PrefUtils.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B8241CDE58F7AAF89AE4 /* PrefUtils.swift */; };
 		1929B5543B1E31A26096E656 /* FileMonitorReducer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B04EC69F616EEFAF5F96 /* FileMonitorReducer.swift */; };
 		1929B59FA5C286E010F70BEE /* Types.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929BFC0A5A9C6DB09BE1368 /* Types.swift */; };
+		1929B5A2EE366F79ED32744C /* KeysPrefReducer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B88B5FA08E897A3C2168 /* KeysPrefReducer.swift */; };
 		1929B5C1BABBC0D09D97C3EF /* PreviewService.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B617C229B19DB3E987B8 /* PreviewService.swift */; };
 		1929B5F016431A76292D1E84 /* FileMonitor.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B365A6434354B568B04F /* FileMonitor.swift */; };
 		1929B6388EAF16C190B82955 /* FileItemIgnorePattern.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B69499B2569793350CEC /* FileItemIgnorePattern.swift */; };
@@ -48,6 +49,7 @@
 		1929B71610FF1DC6E459BA49 /* PreviewUtils.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B8EF9A9F5ACC175452BD /* PreviewUtils.swift */; };
 		1929B8DDACEB28E6672AEC42 /* MainWindow.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B6E01216D49BB9F3B6A3 /* MainWindow.swift */; };
 		1929B8E90A1378E494D481E7 /* PrefUtilsTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B7BB3E4B3DC96284B686 /* PrefUtilsTest.swift */; };
+		1929B8F498D1E7C53F572CE2 /* KeysPref.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B14A5949FB64C4B2646F /* KeysPref.swift */; };
 		1929B8FB248D71BF88A35761 /* PreviewTool.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B6C6C7792B05164B0216 /* PreviewTool.swift */; };
 		1929B9318D32146D58BB38EC /* AppKitCommons.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4B6A70931D60E04200E12030 /* AppKitCommons.swift */; };
 		1929B94083273D4B321AD848 /* FileItemUtils.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B56C8ED31834BA9D8543 /* FileItemUtils.swift */; };
@@ -66,7 +68,6 @@
 		1929BD2F41D93ADFF43C1C98 /* NetUtils.m in Sources */ = {isa = PBXBuildFile; fileRef = 1929B02440BC99C42F9EBD45 /* NetUtils.m */; };
 		1929BD3878A3A47B8D685CD2 /* AppDelegateReducer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B7A68B7109CEFAF105E8 /* AppDelegateReducer.swift */; };
 		1929BD3F9E609BFADB27584B /* Scorer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B9D510177918080BE39B /* Scorer.swift */; };
-		1929BD9AEB34F95438D97FE7 /* KeysPref.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B461EB3DE08C58DD9ED9 /* KeysPref.swift */; };
 		1929BDFDBDA7180D02ACB37E /* RxSwiftCommonsTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B6C215ACCBE12672A8D7 /* RxSwiftCommonsTest.swift */; };
 		1929BE0DAEE9664C5BCFA211 /* States.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929BB6608B4F0E037CA0F4C /* States.swift */; };
 		1929BE0F64A6CE5BCE2A5092 /* MainWindow+Delegates.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1929B714EB137AE448CE8ABD /* MainWindow+Delegates.swift */; };
@@ -223,13 +224,13 @@
 		1929B0FBFB766042CF06E463 /* AppearancePref.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AppearancePref.swift; sourceTree = "<group>"; };
 		1929B11D672134E52A256A7F /* UrlCommonsTest.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UrlCommonsTest.swift; sourceTree = "<group>"; };
 		1929B12CE56A9B36980288A4 /* OpenQuicklyReducer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = OpenQuicklyReducer.swift; sourceTree = "<group>"; };
+		1929B14A5949FB64C4B2646F /* KeysPref.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = KeysPref.swift; sourceTree = "<group>"; };
 		1929B1558455B3A74D93EF2A /* OpenQuicklyFileViewRow.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = OpenQuicklyFileViewRow.swift; sourceTree = "<group>"; };
 		1929B1DC584C89C477E83FA2 /* HttpServerService.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = HttpServerService.swift; sourceTree = "<group>"; };
 		1929B34FC23D805A8B29E8F7 /* Context.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Context.swift; sourceTree = "<group>"; };
 		1929B364460D86F17E80943C /* PrefService.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PrefService.swift; sourceTree = "<group>"; };
 		1929B365A6434354B568B04F /* FileMonitor.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FileMonitor.swift; sourceTree = "<group>"; };
 		1929B457B9D0FA4D21F3751E /* UiRootReducer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UiRootReducer.swift; sourceTree = "<group>"; };
-		1929B461EB3DE08C58DD9ED9 /* KeysPref.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = KeysPref.swift; sourceTree = "<group>"; };
 		1929B49E6924847AD085C8C9 /* PrefWindowReducer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PrefWindowReducer.swift; sourceTree = "<group>"; };
 		1929B5046239709E33516F5C /* Pref128ToCurrentConverter.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Pref128ToCurrentConverter.swift; sourceTree = "<group>"; };
 		1929B56C8ED31834BA9D8543 /* FileItemUtils.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FileItemUtils.swift; sourceTree = "<group>"; };
@@ -252,6 +253,7 @@
 		1929B8042AC566CDF6C998A3 /* FileUtilsTest.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FileUtilsTest.swift; sourceTree = "<group>"; };
 		1929B8241CDE58F7AAF89AE4 /* PrefUtils.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PrefUtils.swift; sourceTree = "<group>"; };
 		1929B85023B042C485409CE1 /* HtmlPreviewTool.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = HtmlPreviewTool.swift; sourceTree = "<group>"; };
+		1929B88B5FA08E897A3C2168 /* KeysPrefReducer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = KeysPrefReducer.swift; sourceTree = "<group>"; };
 		1929B8EF9A9F5ACC175452BD /* PreviewUtils.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PreviewUtils.swift; sourceTree = "<group>"; };
 		1929B9355C892BEBA7496C71 /* DictionaryCommonsTest.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DictionaryCommonsTest.swift; sourceTree = "<group>"; };
 		1929B9AF20D7BD6E5C975128 /* FoundationCommons.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FoundationCommons.swift; sourceTree = "<group>"; };
@@ -388,7 +390,6 @@
 				1929BCE3E156C06EDF1F2806 /* FileOutlineView.swift */,
 				1929BA5C7099CDEB04B76BA4 /* FileBrowser.swift */,
 				1929BD2CA8DD198A6BCDBCB7 /* ThemedTableSubviews.swift */,
-				1929B461EB3DE08C58DD9ED9 /* KeysPref.swift */,
 			);
 			name = "File Browser";
 			sourceTree = "<group>";
@@ -482,6 +483,7 @@
 				1929BED01F5D94BFCA4CF80F /* AppearancePrefReducer.swift */,
 				1929B7039C5689CE45F53888 /* AdvancedPrefReducer.swift */,
 				1929B694508FB5FDE607513A /* ToolsPrefReducer.swift */,
+				1929B88B5FA08E897A3C2168 /* KeysPrefReducer.swift */,
 			);
 			name = Preferences;
 			sourceTree = "<group>";
@@ -506,6 +508,7 @@
 				1929B0FBFB766042CF06E463 /* AppearancePref.swift */,
 				1929BBE0A534F2F6009D31BE /* AdvencedPref.swift */,
 				1929BB2AD21A10A0ECA66A5E /* ToolsPref.swift */,
+				1929B14A5949FB64C4B2646F /* KeysPref.swift */,
 			);
 			name = Preferences;
 			sourceTree = "<group>";
@@ -916,7 +919,8 @@
 				1929B8DDACEB28E6672AEC42 /* MainWindow.swift in Sources */,
 				1929B5257DB27F03C6663482 /* MainWindow+Actions.swift in Sources */,
 				1929BE0F64A6CE5BCE2A5092 /* MainWindow+Delegates.swift in Sources */,
-				1929BD9AEB34F95438D97FE7 /* KeysPref.swift in Sources */,
+				1929B8F498D1E7C53F572CE2 /* KeysPref.swift in Sources */,
+				1929B5A2EE366F79ED32744C /* KeysPrefReducer.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
diff --git a/VimR/VimR/KeysPrefReducer.swift b/VimR/VimR/KeysPrefReducer.swift
new file mode 100644
index 00000000..72e22581
--- /dev/null
+++ b/VimR/VimR/KeysPrefReducer.swift
@@ -0,0 +1,29 @@
+/**
+ * Tae Won Ha - http://taewon.de - @hataewon
+ * See LICENSE
+ */
+
+import Foundation
+
+class KeysPrefReducer {
+
+  typealias Pair = StateActionPair<AppState, KeysPref.Action>
+
+  func reduce(_ pair: Pair) -> Pair {
+    var state = pair.state
+
+    switch pair.action {
+
+    case let .isLeftOptionMeta(value):
+      state.mainWindowTemplate.isLeftOptionMeta = value
+      state.mainWindows.keys.forEach { state.mainWindows[$0]?.isLeftOptionMeta = value  }
+
+    case let .isRightOptionMeta(value):
+      state.mainWindowTemplate.isRightOptionMeta = value
+      state.mainWindows.keys.forEach { state.mainWindows[$0]?.isRightOptionMeta = value  }
+
+    }
+
+    return StateActionPair(state: state, action: pair.action)
+  }
+}