Cito uma resposta de Como remover uma ou todas as entradas de texto de preenchimento automático no Chrome?
Linux and Windows
Just highlight it in the dropdown list (using the arrow keys, or your mouse cursor) and press delete on your keyboard.
Note that you may have to press shift+delete in some cases, like if the autocomplete is in the address bar (URL) field.
Mac
Start typing so that the unwanted autocomplete URL comes up.
Hit fn+shift+delete if you have a compact keyboard or shift+delete ⌦ if you have a keyboard with separate delete ⌦ key (and no fn). If you have a non-Apple keyboard, shift+delete should do the trick.
No seu caso, você não tem um botão de exclusão no seu teclado.
Macbook pros do not have a delete key. They have a backspace key, but in the US version only, the word "delete" is written on it. It still works as a backspace key, and you still have to use the fn key to get it to work as a delete key.