I tested the described scenario on my end, however I was not able to observe a problem with the IsSynchronizedWithCurrentItem property. On my end the SelectedItem and CurentItem objects are synchronized as intended.
That is why I am attaching the sample project that I used for testing purposes. Can you check it out and see how it differs from the setup on your end? Should you need any further assistance, can you let me know how I can replicate the scenario in the shared sample project? Note, that you can also update the project and send it over in a new support ticket (since project files cannot be attached to forum posts). This will hopefully allow me to investigate the scenario and better assist you.
I am looking forward to your reply.
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