I am repeatedly faced with the same problem:
- Go on a page (not logged in),
- Click "Add a comment",
- A pop-up appears,
- Click on "Sign up using Stack Exchange",
- "Sigh… I mixed "sign up" and "log in" once again",
- Click on "Log in",
- Log in,
- "I am logged in, but, this is not the page where I wanted to leave a comment, this is the front page !"
I'm not sure this can be easily corrected, but I guess that on the page https://tex.stackexchange.com/users/login?returnurl=… the link on "sign up" ( https://tex.stackexchange.com/users/signup ) should just be modified as https://tex.stackexchange.com/users/signup?returnurl=…
A reason why I always make that confusion: at https://tex.stackexchange.com/users/login, it is written "Log in" then "Sign up", whereas the pop-up that appears says "Sign up or log in" (i.e. the opposite order).
Edit: I think this question should be migrated to meta.sxe, and is not meta.tex.sxe specific.