diff --git a/java/src/com/android/inputmethod/keyboard/Key.java b/java/src/com/android/inputmethod/keyboard/Key.java
index d160038ad..1550e77e3 100644
--- a/java/src/com/android/inputmethod/keyboard/Key.java
+++ b/java/src/com/android/inputmethod/keyboard/Key.java
@@ -105,7 +105,7 @@ public class Key implements Comparable<Key> {
     /** Hit bounding box of the key */
     public final Rect mHitBox = new Rect();
 
-    /** More keys */
+    /** More keys. It is guaranteed that this is null or an array of one or more elements */
     public final MoreKeySpec[] mMoreKeys;
     /** More keys column number and flags */
     private final int mMoreKeysColumnAndFlags;
diff --git a/java/src/com/android/inputmethod/keyboard/KeyboardView.java b/java/src/com/android/inputmethod/keyboard/KeyboardView.java
index e4e75c342..7941fcba2 100644
--- a/java/src/com/android/inputmethod/keyboard/KeyboardView.java
+++ b/java/src/com/android/inputmethod/keyboard/KeyboardView.java
@@ -497,7 +497,7 @@ public class KeyboardView extends View {
             }
         }
 
-        if (key.hasPopupHint() && key.mMoreKeys != null && key.mMoreKeys.length > 0) {
+        if (key.hasPopupHint() && key.mMoreKeys != null) {
             drawKeyPopupHint(key, canvas, paint, params);
         }
     }
diff --git a/java/src/com/android/inputmethod/keyboard/PointerTracker.java b/java/src/com/android/inputmethod/keyboard/PointerTracker.java
index 71b885c0c..5a2af8015 100644
--- a/java/src/com/android/inputmethod/keyboard/PointerTracker.java
+++ b/java/src/com/android/inputmethod/keyboard/PointerTracker.java
@@ -1306,9 +1306,15 @@ public final class PointerTracker implements PointerTrackerQueue.Element {
     }
 
     private void startLongPressTimer(final Key key) {
-        if (key != null && key.isLongPressEnabled() && !sInGesture) {
-            mTimerProxy.startLongPressTimer(this);
-        }
+        if (sInGesture) return;
+        if (key == null) return;
+        if (!key.isLongPressEnabled()) return;
+        // Caveat: Please note that isLongPressEnabled() can be true even if the current key
+        // doesn't have its more keys. (e.g. spacebar, globe key)
+        // We always need to start the long press timer if the key has its more keys regardless of
+        // whether or not we are in the sliding input mode.
+        if (mIsInSlidingKeyInputFromModifier && key.mMoreKeys == null) return;
+        mTimerProxy.startLongPressTimer(this);
     }
 
     private void detectAndSendKey(final Key key, final int x, final int y, final long eventTime) {