I’m using kicad-nightly, and when I export gerbers and view them at jlcpcb, all of the pads that have a roundrect shape show up incorrectly. Here’s how jlcpcb interprets it:
I believe there was recently some discussion saying that companies online gerber viewer is pretty much broken. Check a few other online gerber viewers if in doubt. I think even the picture you posted reminds me of the other thread.
Also complain about this by jlcpb.
Write lengthy emails, grab your phone.
The more they get irritated by this, the more likely they are finally going to do something about it (hopefullly)