It’s not hard to keep track of the last line sent. The difficulty is was the line executed or not.
In the general case, the line might be compound (G code allow multiple commands on a line), or might be defining a zero (G 54… G59). Any uncertainty could lead to a crash or serious problem.
While I agree there should be a way to take off again from a good point, doing so after a hang or crash isn’t that safe a things to do automatically.
The number of reports of hangs - particularly on the Mac - is becoming alarming. We should find the root cause and fix that!
Anyone having Mac hangs, please get a ground/neutral tester (if you don’t already have one) and check all your outlets. Any problems can potentially be fatal and can easily cause untold problems.
Power is often the source of many problems. I documented things to try here:
mark