diff --git a/app/src/main/java/helium314/keyboard/latin/RichInputConnection.java b/app/src/main/java/helium314/keyboard/latin/RichInputConnection.java
index 7d34df49b..f7e8bcc03 100644
--- a/app/src/main/java/helium314/keyboard/latin/RichInputConnection.java
+++ b/app/src/main/java/helium314/keyboard/latin/RichInputConnection.java
@@ -439,7 +439,7 @@ public final class RichInputConnection implements PrivateCommandPerformer {
         // test for this explicitly)
         if (INVALID_CURSOR_POSITION != mExpectedSelStart
                 && (cachedLength >= n || cachedLength >= mExpectedSelStart)) {
-            final StringBuilder s = new StringBuilder(mCommittedTextBeforeComposingText);
+            final StringBuilder s = new StringBuilder(mCommittedTextBeforeComposingText.toString());
             // We call #toString() here to create a temporary object.
             // In some situations, this method is called on a worker thread, and it's possible
             // the main thread touches the contents of mComposingText while this worker thread