On the download page itself there are per-version release notes at the bottom of the page. For example:
Toastify 1.6.9
We're on a roll of a releases!
WI 13235 - thanks to some undocumented API goodness we now have high quality album art, sans little Spotify icon! Thanks Eater!
Bug 13208 - Added some extra code to try to force the Toast window to stay on top, looking for feedback to see if this works otherwise we'll have to look into more drastic measures.
WI 13228 - Tweaks to the paste code to increase reliability of the "paste current song" hotkey
Toastify 1.6.9
We're on a roll of a releases!
WI 13235 - thanks to some undocumented API goodness we now have high quality album art, sans little Spotify icon! Thanks Eater!
Bug 13208 - Added some extra code to try to force the Toast window to stay on top, looking for feedback to see if this works otherwise we'll have to look into more drastic measures.
WI 13228 - Tweaks to the paste code to increase reliability of the "paste current song" hotkey