1.3 for Minecraft Java 26.3

Added ~100 blocks
Added 23 items

Changed 64 blocks
Changed 44 items

(These figures may be slightly off, as I may have accidentally missed things when adding everything up).

Added: 
- All remaining shelves (12)
- Chiseled resin bricks
- Lever
- Resin Block
- Brush
- Spears (7) 
- Wind Charge
- Ominous Bottle
- Potion particles
- Copper Grates (4)
- Nautilus Shell
- Nautilus Armors (5)
- Dry Grass (2)
- Cinnabar tileset (4)
- Sulfur tileset (4)
- Potent Sulfur
- Suspicious Sand/Gravel (2)
- Copper Bulbs (4)
- Chiseled Copper Blocks (4)
- Daylight Sensor
- Note Block
- Jukebox
- Cactus
- Dispenser
- Dropper
- Enchantment Table
- Copper Trapdoors (4) 
- Crimson and Mangrove Trapdoors (2)
- Mob Spawner
- Heavy Core
- Scaffolding
- Firework Crossbow
- Signs (block) (13)
- Poplar Log
- Poplar Planks
- Stripped Poplar Log
- Poplar Trapdoor
- Mangrove Roots (2)
- Poplar Door
- Smithing Table
- Lanterns (6)
- Poplar Sign (item)
- Blast Furnace
- Smoker
- Grindstone
- Vines
- Music Discs "Bounce" and "5" (2)
- Disc Fragment "5"
- Bee Nest
- Chiseled Bookshelf
- Hopper (block)
- Glow Lichen
- Cartography Table
- End Portal Frame
- Frosted Ice
- Observer
- Redstone Repeater (block)
- Tripwire Hook
- Target Block
- Sculk Vein
- Poplar Boat (item)
- Redstone Comparator (block)

Changed: 
- Coal Block
- Hanging Roots
- Pistons (2)
- Sea Lantern
- Polished Tuff
- Diamond (item)
- Emerald (item)
- Echo Shard
- Glow Berries (item)
- Quartz (item)
- Shovels (7) 
- Crossbow
- Armor models
- Bamboo Log
- Ender Pearl
- Most GUIs
- Basalt
- Bread
- Magma Cream
- Oxidized Copper Bars
- Nether Quartz Ore
- Apples (2)
- Slimeball
- Mace
- Swords (7)
- Budding Amethyst (block)
- Bottle o' Enchanting
- Chiseled Deepslate
- Block of Raw Gold
- Oak Shelf
- Deepslate
- All deepslate ores (8)
- Furnace
- Honey Block
- Slime Block
- Sugar Cane (block)
- Gilded Blackstone
- Lapis Ore
- Flower Pot (item)
- Bamboo Planks
- Stripped Bamboo Log
- Fishing Rod
- Deepslate Tiles
- Cracked Deepslate Tiles
- Red Mushroom Block
- Smooth Basalt
- Ender Chest
- Clay (block)
- Block breaking indicator
- Sponge
- Wet Sponge
- Beds (16)
- Prismarine Bricks
- Tall Grass (2)
- Snow
- Snowy Grass
- Stonecutter
- Boats (item) (9)
- Beetroot Seeds
- Crimson and Warped Signs (item) (2)
- Redstone Repeater (item)
- Redstone Comparator (item)
- Quartz Bricks
- Mud
- Packed Mud