DlgTrackInfo: prevent wipe when quickly applying twice

Fixes mixxxdj#12963

src/library/dlgtrackinfo.cpp

@@ -613,6 +613,13 @@ void DlgTrackInfo::saveTrack() {
     slotSpinBpmValueChanged(spinBpm->value());
     static_cast<void>(updateKeyText()); // discard result
 
+    // Don't update if nothing changed. This prevents wiping the record
+    // when calling this function twice quickly.
+    // See https://github.com/mixxxdj/mixxx/issues/12963
+    if (m_trackRecord == m_pLoadedTrack->getRecord()) {
+        return;
+    }
+
     // Update the cached track
     // The dialog is updated and repopulated by the Track::changed() signal.
     m_pLoadedTrack->replaceRecord(std::move(m_trackRecord), std::move(m_pBeatsClone));