diff --git a/widget/gtk/IMContextWrapper.cpp b/widget/gtk/IMContextWrapper.cpp
index aa2f6cddb26d7..e14c2b37c4436 100644
--- a/widget/gtk/IMContextWrapper.cpp
+++ b/widget/gtk/IMContextWrapper.cpp
@@ -1559,10 +1559,18 @@ IMContextWrapper::DispatchCompositionCommitEvent(
 
     RefPtr<nsWindow> lastFocusedWindow(mLastFocusedWindow);
 
+    // Emulate selection until receiving actual selection range.
+    mSelection.CollapseTo(
+        mCompositionStart +
+            (aCommitString ? aCommitString->Length() :
+                             mDispatchedCompositionString.Length()),
+        mSelection.mWritingMode);
+
     mCompositionState = eCompositionState_NotComposing;
     mCompositionStart = UINT32_MAX;
     mCompositionTargetRange.Clear();
     mDispatchedCompositionString.Truncate();
+    mSelectedStringRemovedByComposition.Truncate();
 
     nsEventStatus status;
     rv = dispatcher->CommitComposition(status, aCommitString);
diff --git a/widget/gtk/IMContextWrapper.h b/widget/gtk/IMContextWrapper.h
index c18ff9fdbf1b3..adcc02854d998 100644
--- a/widget/gtk/IMContextWrapper.h
+++ b/widget/gtk/IMContextWrapper.h
@@ -231,6 +231,13 @@ class IMContextWrapper final : public TextEventDispatcherListener
             mOffset = UINT32_MAX;
             mWritingMode = WritingMode();
         }
+        void CollapseTo(uint32_t aOffset,
+                        const WritingMode& aWritingMode)
+        {
+            mWritingMode = aWritingMode;
+            mOffset = aOffset;
+            mString.Truncate();
+        }
 
         void Assign(const IMENotification& aIMENotification);
         void Assign(const WidgetQueryContentEvent& aSelectedTextEvent);