Ticket #21507: 21507.patch

src/org/openstreetmap/josm/gui/tagging/ac/AutoCompTextField.java

@@ -157 +157 @@
         if (unSelected.length() <= oldText.length())
             // do not autocomplete on control or deleted chars
             return;
+        if (getInputMethodRequests().getCommittedTextLength() != getDocument().getLength()) {
+            // do not autocomplete if there is uncommitted text (breaks Microsoft Japanese IME, see #21507)
+            return;
+        }
         if (!AUTOCOMPLETE_NUMBERS && IS_NUMBER.matcher(newText).matches())
             return;