Should

$(test)

not be

$("#test")

Thanks for your answer,

With $("#test") we have the same result on Firefox and IE, but not with $(test).

Maybe it's normal, I don't know, but in any case, what is test in $(test) and why IE process it differently ?

Do you think it's a problem of browser or in jQuery ?

$(test)

is wrong scripting.

test

is a variable, but in the whole document not defined. So jQuery is looking for something that doesn't exist.

Why it does work on some browsers is weird.

To conclude it's not a jQuery bug, nor a browser bug, it's wrong scripting.