docker: invalid reference format: repository name must be lowercase.

When trying to create a new Laravel project on Windows 10 in WSL 2 Ubuntu using Docker (following Laravel Getting started -> Installation tutorial), I've been getting this error: "docker: invalid reference format: repository name must be lowercase."

I found out why I've been getting this error, it's because my Windows username contains 2 words (space) and has uppercase letters. After I created another local Windows account with only lowercase letters and one word, and repeated installation of WSL 2 and Ubuntu, no errors anymore and everything worked immediately. I hope it helps someone struggling with this.

Also I couldn't find out what the error was for some time until I removed -s from "curl -s ... | bash" when installing so I suggest there's no -s argument in official installation documentation for easier debugging and error handling.