In the creative menu, when you type in certain letters to look up a block, it wont work. For me, if I type any of these letters, the display of blocks doesn't change as it would normally (if I type "a" everything with the letter "a" in it will appear, but it stays the same as if it doesn't recognize what I am typing.]
These Letters seem to be effected:
a, c, f, i, m, n, r, and t.
Great update, and I hope this helped fix Minecraft 1.8!
Based on what letters are affected ('e' is affected as well), I believe it's because it's trying to match the "minecraft:" prefix - indeed, all the letters you listed are in the word "minecraft". I'm guessing this was intentional, but maybe it's not.