https://wccftech.com/borderlands-3-update-4-raid-bank-expansion/

Borderlands 3 has dropped its latest update, and it’s a big one. In terms of fresh content, the update adds the “Takedown at the Maliwan Blacksite” raid and the new Mayhem 4 difficulty. Some much-needed improvements include expanded capacity for your weapon bank on Sanctuary III (you can now hold up to 100 items), a target dummy to test out guns on, more vending machines for longer levels, better performance for the game’s previously-sluggish menus, and more. All very-much-appreciated changes!

You can check out the full notes for Borderlands 3 Patch 4 below: