1.9, known as The Combat Update[1], is an upcoming update to Minecraft with no set release date, currently only listed in the bug tracker as "Far Future Version - 1.9+"[2], as well as mentioned by the Minecraft developers.
MC-14525 – Name tag doesn't work on entities with right click ability.
MC-16204 – New creative GUI showing detailed effects does not show on some potions. Neither to bows.
MC-28479 – Chest interface not closed when chest is blocked from opening.
MC-42841 – Incorrect creative instant health damage value.
MC-52802 – Mob head takes a fraction of a second to change to selected head.
MC-54486 – Glass panes and iron bars don't connect to graphically opaque blocks that are registered as transparent. e.g. slime blocks, ender portal frame blocks and monster spawner blocks.
MC-55942 – Nether Wart hitbox is incorrect on multiplayer. (Untested on singleplayer.)
MC-67163 – Damage value for objective stat.mineBlock is missing.
MC-68062 – Boss health bar only visible when looking at boss
MC-75082 – End music will stop every time the ender dragon loads out of view.
Trivia
1.9's title, The Combat Update, was discovered in Mojang's April Fool's prank snapshot, 15w14a, by how snow was coded to form a QR code that could be scanned to find the title. Dinnerbone later confirmed that this wasn't a joke.[27]