One of the worst sites in existence is the Japanese Visa site they direct people to to make QR codes for when you land in Japan as a tourist. It's atrocious.
https://services.digital.go.jp/en/visit-japan-web/
I hate it so much I kind of wish I could volunteer to fix it. I suspect the process though would be torture
Note: experience on mobile is bad. I don't remember if desktop is better.
I live in Japan and every time I go through the airport I refuse to use the QR code customs forms, the old paper based form is so much easier...