diff --git a/Source/Modules/ControllerModules/ctlInputMethod_Core.swift b/Source/Modules/ControllerModules/ctlInputMethod_Core.swift
index fa8c578e..91265975 100644
--- a/Source/Modules/ControllerModules/ctlInputMethod_Core.swift
+++ b/Source/Modules/ControllerModules/ctlInputMethod_Core.swift
@@ -27,9 +27,6 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 import Cocoa
 import InputMethodKit
 
-/// 最小選字鍵字號。
-private let kMinKeyLabelSize: CGFloat = 10
-
 /// 目前在用的的選字窗副本。
 private var ctlCandidateCurrent = ctlCandidateUniversal.init(.horizontal)
 
@@ -488,7 +485,7 @@ extension ctlInputMethod {
 
     // set the attributes for the candidate panel (which uses NSAttributedString)
     let textSize = mgrPrefs.candidateListTextSize
-    let keyLabelSize = max(textSize / 2, kMinKeyLabelSize)
+    let keyLabelSize = max(textSize / 2, mgrPrefs.minKeyLabelSize)
 
     func labelFont(name: String?, size: CGFloat) -> NSFont {
       if let name = name {
diff --git a/Source/Modules/IMEModules/mgrPrefs.swift b/Source/Modules/IMEModules/mgrPrefs.swift
index 6bf13e1f..61ef3134 100644
--- a/Source/Modules/IMEModules/mgrPrefs.swift
+++ b/Source/Modules/IMEModules/mgrPrefs.swift
@@ -75,7 +75,7 @@ struct UserDef {
 }
 
 private let kDefaultCandidateListTextSize: CGFloat = 18
-private let kMinKeyLabelSize: CGFloat = 10
+private let kDefaultMinKeyLabelSize: CGFloat = 10
 private let kMinCandidateListTextSize: CGFloat = 12
 private let kMaxCandidateListTextSize: CGFloat = 196
 
@@ -331,6 +331,8 @@ public enum mgrPrefs {
   @CandidateListTextSize(key: UserDef.kCandidateListTextSize)
   static var candidateListTextSize: CGFloat
 
+  static var minKeyLabelSize: CGFloat { kDefaultMinKeyLabelSize }
+
   @UserDefault(key: UserDef.kShouldAutoReloadUserDataFiles, defaultValue: true)
   static var shouldAutoReloadUserDataFiles: Bool