Email or Username: A.J.Caines+Lemmy@example.com
Password: *password123*

Incorrect login credentials

but

Email or Username: a.j.caines+lemmy@example.com
Password: *password123*

Logged in

While the forty-year-old standard for email specifies the left hand side of the @ as case sensitive, the de facto standard is to treat email addresses as case insensitive - preferably with normalisation handled outside the user interface (by lowering (unless you are Oracle)).

Tested with UI: 0.19.0-rc.9 BE: 0.19.0-rc.8