Pressing F3 (or whichever key is assigned to to slot #3 on the special bar) causes the player to start attacking nearby targets (including neutral targets). This seems to happen with every profession (ex., elementalist switching to air attunement) but is particularly nonsensical with rangers, since F3 is used to recall the pet and prevent it from attacking (so players successfully prevent the pet from pulling an enemy and then pull it themselves, involuntarily).
- Al Zheimer