diff --git a/Source/Modules/IMEModules/ctlInputMethod.swift b/Source/Modules/IMEModules/ctlInputMethod.swift
index 6713f2dc..d2566dd6 100644
--- a/Source/Modules/IMEModules/ctlInputMethod.swift
+++ b/Source/Modules/IMEModules/ctlInputMethod.swift
@@ -195,13 +195,12 @@ class ctlInputMethod: IMKInputController {
         // 同時注意：必須將 event.type == .flagsChanged 放在最外圍、且在其結尾插入 return false，
         // 否則，每次處理這種判斷時都會觸發 NSInternalInconsistencyException。
         if (mgrPrefs.functionKeyboardLayout != mgrPrefs.basisKeyboardLayout) && (event.type == .flagsChanged) {
-            let includeShift = mgrPrefs.functionKeyKeyboardLayoutOverrideIncludeShiftKey
             if (event.modifierFlags == .capsLock ||
                 event.modifierFlags.contains(.command) ||
                 event.modifierFlags.contains(.option) ||
                 event.modifierFlags.contains(.control) ||
                 event.modifierFlags.contains(.function) ||
-                       (event.modifierFlags.contains(.shift) && includeShift)) {
+                       (event.modifierFlags.contains(.shift) && mgrPrefs.functionKeyKeyboardLayoutOverrideIncludeShiftKey)) {
                 (client as? IMKTextInput)?.overrideKeyboard(withKeyboardNamed: mgrPrefs.functionKeyboardLayout)
             } else {
                 (client as? IMKTextInput)?.overrideKeyboard(withKeyboardNamed: mgrPrefs.basisKeyboardLayout)