I was playing on creative and tried to place an anvil, and i couldn't place it, it would only break the block I was looking at. Then I tried placing something else, that didn't work either. I went to my controls and tried to change the Pick block, Place Block, and Attack buttons to see what i could do in my power to fix it, but it only made it worse. YOU CAN'T USE BUTTON 2 OR 3! to make it simpler, when trying to put the controls back to normal i would only get button 1, when clicking LControl / RControl whichever you use, with a Click of the mouse at the same time. If you do not have a mouse that has the left button & right button, then you cannot change your controls back to normal. This is a very serious bug, Since this deals with the three most used buttons in the game! ...but I'm not sure if this has happened to anyone else if it has then i'm awesome