The Secondary Mouse Button could not be used for "Fire Weapon" if the weapon has a auto-firing mode.
The bug is in Arma since Arma II. Please see also the following report i've made for Arma II 4 years (!) ago:
The Secondary Mouse Button could not be used for "Fire Weapon" if the weapon has a auto-firing mode.
The bug is in Arma since Arma II. Please see also the following report i've made for Arma II 4 years (!) ago:
Assign the secondary mouse button to "fire weapon" and try to shoot a weapon in auto fire mode (==hold it pressed to fire rounds)
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