In circulation when the item transfer prompt appeared, you have to press <ALT> + Y (or click "OK" with the mouse) to acknowledge. It will be nice that we can just press "Y" without using <ALT> key. This is particularly helpful when you are holding a barcode scanner a hand.
The keyboard shortcuts for buttons like that use HTML's accesskey attribute, which means that the keyboard combination may vary based on the browser you're using. For instance, in Firefox on a Mac it's even more convoluted: Ctrl + Alt + Y. We could implement those shortcuts in JavaScript but we must be conscious of accessibility concerns: https://webaim.org/techniques/keyboard/accesskey#alternatives