diff --git a/changelog.txt b/changelog.txt
index 46e84e18..d0770e88 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -3,11 +3,19 @@ OPENSEADRAGON CHANGELOG
 
 1.0.0: (in progress)
 
+* BREAKING CHANGE: Renamed EventHandler to EventSource (#225)
+* BREAKING CHANGE: MouseTracker event handler method signatures changed to 'handlerMethod( tracker, eventData)' (#23)
+* BREAKING CHANGE: Button event names changed to lower case, removed "on" prefix (#226):
+*     "onPress" is now "press"
+*     "onRelease" is now "release"
+*     "onClick" is now "click"
+*     "onEnter" is now "enter"
+*     "onExit" is now "exit"
+*     "onFocus" is now "focus"
+*     "onBlur" is now "blur"
 * MouseTracker now passes the original event objects to its handler methods (#23)
-* Breaking change: MouseTracker event handler method signatures changed to 'handlerMethod( tracker, eventData)' (#23)
 * MouseTracker now supports an optional 'moveHandler' method for tracking mousemove events (#215)
 * Fixed: Element-relative mouse coordinates now correct if the element and/or page is scrolled (using new OpenSeadragon.getElementOffset() method) (#131)
-* Renamed EventHandler to EventSource (#225)
 
 0.9.131: