I have followed your reproduction steps and still have not had any issues navigating the Blueprint graph when hitting PIE from the editor viewport.
Could you try closing out of all software that is running on your PC and then run the editor so that it is the only application open. If you are still experiencing problems please let me know. If this happens to fix your issue enable your other applications one by one until you find what is causing the problem and please let me know what was causing it.
Thank you.