My current weapon is a shotgun and I am using the right mouse button for Weapon Attack.
If I keep the right mouse button pushed, my character keeps firing, and that works while moving the mouse cursor anywhere on the screen.
But if the mouse cursor is above an enemy, after shooting and killing it, I move the cursor over the next enemy to keep shooting, but my character stops firing. I have to click the right mouse button again to shoot the next enemy.
If I could keep shooting by simply holding the right mouse button pressed, the gameplay would be much more smooth. If you fight a large group of enemies, why to click 30 times when you can simply keep the mouse button pushed until all the enemies are all dead?
Sounds like you are using the “Classic” control scheme. Go to settings and change it to the “New” scheme. At least for me it just locks on to whatever your mouse is hovering over keeps firing. The new scheme is a bit iffy for ranged in a big mob because it will lock on and auto shoot anything while you are running around, so if you accidentally pass over an enemy or an attackable world item while trying to maneuver you will stop running and autofire. The standing attack key helps a lot, and prevents jerky movement in big mobs while attacking in “New” mode.