Workaround for the shrinking friends list box when sending gifts and train boosts
This is working for some users, we are not sure if it will work for everyone but it's worth a try.
When you get the box that comes up with your friends in it, quickly "right click" your mouse on the "All Farmers" at the top left of the box, and then choose "open in a new tab". You should then get a full size window that does not shrink allowing you to click the "Send" button.