Problems with changing publication's name

Guys, am I the only who have such problem: when trying to change name for publication for solved task it doesn't let me to do this in an easy way. I have default value for publications - "First". When clicking "Change" button - input field appears, but when I press "Backspace" to erase "First" it removes only last symbol and takes other part ("Firs") as name and so on. Is it bug or I don't understand smth?

I'm using Firefox, if it matters.