A very minor bug, but annoying all the same:
When you go into full dictionary, there is an arrow in the top left corner, and x in the top right corner. In 2.4.0, the arrow would take you into the part of the dictionary where you could edit the input (ie take off the -ed on a verb when the verb wouldn't show in in the dictionary otherwise) and the x would take you back to the book.
The bug? In 2.5.0, BOTH the arrow and the x take you back to the book. Useful, two separate buttons performing the same function.