ctlIME // +useIMKCandidateWindow.

Source/Modules/ControllerModules/ctlInputMethod_Core.swift

@@ -25,7 +25,8 @@ class ctlInputMethod: IMKInputController {
   static var areWeNerfing = false
 
   /// 目前在用的的選字窗副本。
-  static var ctlCandidateCurrent: ctlCandidateProtocol = ctlCandidateIMK.init(.horizontal)
+  static var ctlCandidateCurrent: ctlCandidateProtocol =
+    mgrPrefs.useIMKCandidateWindow ? ctlCandidateIMK.init(.horizontal) : ctlCandidateUniversal.init(.horizontal)
 
   /// 工具提示視窗的副本。
   static let tooltipController = TooltipController()

Source/Modules/ControllerModules/ctlInputMethod_HandleDisplay.swift

@@ -66,13 +66,14 @@ extension ctlInputMethod {
     /// layoutCandidateView 在這裡無法起到糾正作用。
     /// 該問題徹底解決的價值並不大，直接等到 macOS 10.x 全線淘汰之後用 SwiftUI 重寫選字窗吧。
 
-    if isCandidateWindowVertical {  // 縱排輸入時強制使用縱排選字窗
-      ctlInputMethod.ctlCandidateCurrent = ctlCandidateIMK.init(.vertical)
-    } else if mgrPrefs.useHorizontalCandidateList {
-      ctlInputMethod.ctlCandidateCurrent = ctlCandidateIMK.init(.horizontal)
-    } else {
-      ctlInputMethod.ctlCandidateCurrent = ctlCandidateIMK.init(.vertical)
-    }
+    let candidateLayout: CandidateLayout =
+      ((isCandidateWindowVertical || !mgrPrefs.useHorizontalCandidateList)
+        ? CandidateLayout.vertical
+        : CandidateLayout.horizontal)
+
+    ctlInputMethod.ctlCandidateCurrent =
+      mgrPrefs.useIMKCandidateWindow
+      ? ctlCandidateIMK.init(candidateLayout) : ctlCandidateUniversal.init(candidateLayout)
 
     // set the attributes for the candidate panel (which uses NSAttributedString)
     let textSize = mgrPrefs.candidateListTextSize