**[Quick visibility thing – we're posting this in English first but getting it localized for all regions as soon as possible.]**
Due to internal miscommunication, two important changes to Quick Cast shipped in patch 5.7 but never made it into the patch notes.
**So what did we change and why?**
The first change is a bug and affects normal and quick cast with range indicators only. Using the right mouse click to cancel abilities should cancel on **mouse down**, not **mouse up** (as in releasing the button), as you may have noticed. This has made cancelling abilities using the right mouse click difficult and unresponsive.
The second change was intentional for quick cast when used with range indicators. In order to make chucking out a quick series of abilities more responsive and predictable (think Brand, Annie, or Ryze unleashing their combos), we changed this behavior to fire the first ability held down when the second ability is pressed. Basically we assumed that if you pressed a button, you were committed to using that ability (a la quick cast) and if you decided to press another button, that was because you were trying to cast something else.
What we didn't account for was that some players were using quick cast with range indicators in a different way, where they would hold down each button to get the range of the ability before releasing it to pull off a combo. In other words, they were basically 'queueing' up abilities by holding down buttons - releasing a button was their version of "quick cast."
That said, from a lot of discussion it's clear we've introduced tons of disruption without much context for players who used it to test ranges. Sorry!
**So here’s what we’re going to do.**
We are fixing the right mouse cancel bug and re-implementing the old quick cast with range indicator behavior. In other words, abilities will continue to fire on **button release**, rather than on **button press**.
In the meantime, we're going to be re-examining the problem space for players who want to better understand their champion’s ranges while maintaining the responsiveness of true quick cast (that is, on button press). Any future solutions here will not disrupt existing play and most likely live on their own as an option.
One last thing, to alleviate some of the existing pain of using quick cast with range indicators, we’ll be adding individual ability and item binds for this input type in an upcoming patch.
Thanks for your patience and feedback here! We'll be trying to get this in as soon as possible (it could potentially take as long as patch 5.8 due to the scope and stability of the changes, sorry!).
I will be around throughout the day to answer questions or try to give more context into what has changed. I hope this helps clarify things.