Better Inventory And Backpacks

Better Inventory 1.2.0 (NeoForge 1.21.1, Fabric 1.21.1, Forge 1.20.1, Fabric 1.20.1)

• Upgrading a backpack keeps what is in it. Crafting a backpack into the next level now carries its contents, its installed upgrades, its tab settings and its name over to the new one. Before, everything inside the old backpack was lost.
• New layout. The player view (and the crafting panel that takes its place) moved to the left, and the inventory itself now sits in the middle of the screen. The right side is free for JEI, EMI or REI.
• The item zoom is back. Hover an item to see it enlarged in a frame to the right of the inventory. It shows when the screen is wide enough for it; with a recipe viewer installed, only when there is room for both. Client options: zoom.enabled and zoom.scale.
• The button to Minecraft's own inventory is now a slot with two arrows in the bottom row, under the player view, instead of hanging below the panel. The trash slot moved to the bottom right.
• New key: Open the vanilla inventory. Opens Minecraft's own inventory once without switching over to it. It is unbound by default; set it under Controls, Better Inventory.

Per version:

• Fabric 1.21.1 is new. It needs Fabric API. Of the inventory buttons for other mods only Accessories exists on Fabric, and settings are in config/betterinventory.json.
• Forge and Fabric 1.20.1: your own inventory's stack limit now follows the stack upgrade. In the 1.1.5 files it stayed at 64.
• NeoForge 1.21.1 also gets what 1.1.5 brought to 1.20.1: a toolbox slot when Slate Building is installed.