Okay, I don't own any Glocks and I don't own a PPS, I do own a PPQ and it doesn't stay to the rear. Neither does the XD Mod 2, the Shields, HKs or Sigs. I'm not sure why you, some dude I don't know, would give a F about me asking a question about the function of a gun I bought ( ridiculously cheap) that I have never seen on any other gun.
Next. The Shield has a larger grip than the XDs. It fits my hand better. My Shield .45 is a tack driver with zero issues or weird "Functionality" quirks in the close to 10k rounds I've put through it. And it conceals as easily as an XDs. I also pretty easily can conceal a VP9 and even a 4" service model XD Mod 2 .45 in cooler weather. Furthermore, if I need "Deep concealment" I can conceal damn near anything under my armpit. I have shirts for that. AIWB is also a viable option.
It's not your business how many guns I have collected in my 40-ish years of shooting and collecting and I really am not interested or impressed with how many you have. I can think of at least 3 or 4 guys on this forum right here that make your collection and my collection combined look like we just bought our first gun yesterday.
So.. To summarize. I bought an XDs at about 1/5th of the price they sell for. It is not a gun I would buy if I wasn't getting it very cheap. And frankly I did it to help out my brother in law. It has a weird trigger issue I have never seen before, so I guess I have to defer to your incredible base of knowledge with your 100s of firearms. My question, as simple and pedestrian as it is, is do ALL XDs do this ? Is it some sort of magazine disconnect or is their something wrong with this gun ? So if you can answer THAT question I appreciate it. If not, make way for someone who can.