We will think about how to improve this option. thanks

In that this affected me badly as well, I think this shows that some changes are being implemented without a complete understanding of how high performance PCBs are designed. Would it be not be better for users to see a list of things being developed in advance so that comments can be made before time is spent (i.e. wasted) developing things that break designs.  I understand that JLCPCB asked for this feature but I cannot think that any experienced PCB designer would have agreed it was a good idea.  Indeed what we would all like is to have plating along the whole edge of the PCB, but we accept this isn't possible so maximal capacitive connection so as to reduce r.f. leakage from the top to the bottom of the PCB is the next best thing.  This fixed gap you have introduced is effectively a tuned element that could even resonate, breaking all sorts of EMC limits.   Experienced user will add tracking at the PCB edge instead but others may not realise just how essential this is and accept the new copper fill. Can I please ask that you get rid of this feature and go back to the old software.

I suspect the reason that this gap was introduced is to stop people accidentally shorting the copper areas at the board edges to their enclosures.

You're supposed to short (or at least capacitatively couple) PCB edges to the enclosure.  That is why you always run ground planes right to the edge but VCC planes to 5mm away from the edge.

I think a bit of background information might be helpful for some people at this point. The reason for extending the ground plane to the edge of the board but insetting signals and power planes to 5mm or more in from the edge is a simplification of the "10 to 20 times the plane separation" or 20H rule of thumb applied to ground the fringing fields that radiate from the gap between signal traces or power planes and the ground plane. To provide a bit more of an insight into why the 20H rule is applied please see this post in the Tips and Skill section: [https://easyeda.com/forum/topic/The-20H-and-Ground-Plane-Extension-rules-benefits-and-limitations-of-applying-them-4d443d32240545aeb9fa9516d2fdac3f](https://easyeda.com/forum/topic/The-20H-and-Ground-Plane-Extension-rules-benefits-and-limitations-of-applying-them-4d443d32240545aeb9fa9516d2fdac3f)