My second attempt at a mod, which turned out better than the first (less Java jank).

General

Bundles can now always use right-clicks for inserting or removing items.

• Modified via the "KEY_SWAP" config option.
• Default Behavior:
  • Left-clicking the bundle with an item (or vice versa) will attempt to place the item into the bundle.
  • Right-clicking the bundle with an item (or vice versa) will swap the bundle with the item.

Empty bundles can now be picked up and placed using right-click.

• Modified via the "ON_EMPTY" config option.
• Default Behavior:
  • The bundle will remain where it was.

Both of the above options are enabled by default, and can be modified without restarting the game.