This has happened to me a number of times. People fork a GitHub project of mine only to remove the attribution where my name appears. I find it to be rude.
Example: https://github.com/Fordeer/2fa-qr/commit/c2c5321ddb6b5f00246f52fef1cb6977c39c7352
This fork is served at https://2fa.fordeer.io/
My original is served at https://stefansundin.github.io/2fa-qr/
The project is licensed under GPLv3 and there is a LICENSE file in the repository. Besides being bad behavior, is this violating the license?