You can pick up weapons with Activate/Enter/Use key (usually "F", the same you use to enter a vehicle), and drop them with "J" key.
You can store up to 2 handheld weapons, you spawn with the beamlaser as your default weapon. Now you can buy or pick up a second weapon, but if you want to buy some third weapon, you have to drop the laser first.
This script runs each time you buy a weapon and seems to detect if the lazor is not your default weapon (you bought something else), and if it's not, it drops it to make a space for the weapon you just bought.
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