Please do not update, has it adds alot of new blocks and bugfixes. Await until the server updates and we will tell you.
Here are the wiki's updates about this update:
1.4.6
Here is also the link if you wish to see it yourself:
Link to it!New blocks & items
Firework Rocket
Firework Star used to create Firework Rockets
Enchanted Books for enchanting items
Nether Brick Slabs
A surprise for Chests
New chest textures in Christmas.
Gameplay
Improved some enchantments
Unbreaking enchantment for all items with durability[1]. Some unregular tools (e.g. Shears, Fishing rods) requires Enchanted Books.
Silk Touch can now be applied to shears and swords on the anvil using Enchanted Books, cobweb can be harvested this way.
Added Thorns enchantment. When a mob hits the player it gets damage. It can be cast on armor.
Thorns damage is customizable.[2]
Fire Protection now extinguishes players more quickly.
Blast Protection now reduces explosion recoil.
Efficiency on a pickaxe no longer breaks Dirt faster.
Improved drops
3D rendering for dropped items.[3]
Only renders with Fancy graphics.[4]
When pressing CTRL+Q, the player drops a full stack instead of one item.
Items now show their enchantments when dropped on the ground and in items frames, only in fancy graphics mode.
Improved the block placement on chests, crafting tables, furnaces, beacons, anvils, enchantment tables, brewing stands, etc.
When sneaking, the player can place blocks and items on it.
New notice features
Added tool highlight when switching items in the hotbar
To disable it, open options.txt and change heldItemTooltips to false.
Added a notice/warning for users still playing on PowerPCs or Java 5 (Java 1.5)
New Option
Added a option to toggle touchscreen, in game.
NBT code
The blast radius of fireballs a specific Ghast shoots can be customized with an editor.[5]
Bug Fixes[6][7][8]: []
Fixed mouse wrongly positioned in fullscreen
Fixed mobs walking slowly when you hit them
Fixed server/client desync of chests
Fixed flame effect on arrows when fired into a pressure plate and player immediately engages flight mode
Fixed zombies which sometimes stop attacking
Fixed the inability to remove partial XP bars from the "xp -1L" command when you're between level 0 and 1
Fixed arrows shot at Endermen disappearing
Fixed a bug with custom mob spawners not spawning different types of entities correctly
Fixed animals appearing to walk through fences in SP
Fixed some items with multi-layer textures rendering both layers separately when on the ground
Fixed tools differing only in damage not being able to be swapped in the inventory
Fixed some Z-Fighting with the beacon
Fixed some graphical issues in the trading GUI
Fixed /say not showing the text in the original purple color
Fixed placing double slabs ignoring damage value
Fixed minecarts being unable to travel through Nether portals
Fixed lightning not flashing
Fixed the Nether and the End generating random client-side blocks in MP
Fixed FallingSand spawners failing to save properly and causing crashes
Fixed the blocks in lowest layer of the map not being recognized by beacons
Fixed enchantments not showing in Item Frames, but fixed only in fancy graphics mode.
Fixed 1-9 clicking an item out of a furnace not giving XP
Fixed mobs reverting farmland to dirt when mob griefing gamerule is set to false
Fixed setting an Enderman on fire with lava or flint and steel not making it teleport away
Fixed animals on fire not fleeing
Fixed boats being placed in the wrong direction
Fixed Endermen not being able to dodge flaming arrows
Fixed the game auto-selecting the first item on the toolbar when entering the Nether
Fixed leaves having the incorrect tooltip
Fixed drowning in creative mode
Fixed the /enchant command not enchanting with ID 0 (Protection)
Fixed not hearing the XP sound every 5 levels
Fixed minecarts and falling entities jittering
Fixed passive mob spawn eggs not being consumed
Fixed Endermen not opening their mouths when being attacked by other mobs
Fixed F3+B hitboxes rendering invisibility potions
Fixed the Wither sometimes destroying its own star
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