Does “EDID data sent successfully” confirm that my device was rewritten?

No. It confirms that BetterDisplay’s write operation sent the data without reporting a communication error. It does not confirm that the device accepted and stored the new EDID, or that the resulting display configuration works.

Many monitors restrict EDID writing, while some emulators and dongles accept it. A device can ignore the write even though sending succeeds. Follow the app’s request to reconnect the device, then inspect the EDID it reports and compare it with the intended data. Do not treat the send message alone as proof of a change.

Write EDID to Device modifies device memory when supported. Incorrect data or a failed write can leave the device permanently unusable. Reconnecting does not undo a physical rewrite. It is different from applying a temporary custom EDID override on the Mac. Keep the original EDID and follow the EDID reference’s precautions before considering a device write.