How is the QR code generated? Based on app url solely?

I noticed that the QR Code seems to be exactly the same (at 1st glance, at least), if I manage to keep the same url.
Is it pure luck or?
Will it stay that way?
I was not sure, so when I created a mini tutorial video, I didn’t include the QR code together with the url as CTA, but showed it separately from the video in my communication.
In case the QR code risks changing months later, and anyone still having the old one will not access the right app or any at all.
Thks for your insights.
And maybe it would be nice to include the app logo in the middle of the QR code. Or even enable customization of just this central zone?

QR codes are just an encoded string of text. They are just like linear barcodes, but can contain more information in a smaller area. In this case it, contains and encoded version of the app url. If the url doesn’t change, then the qr code won’t change either.