Cursor freezes when casting an ability

It is very annoying. I'll try to describe as well as I can. It may not qualify as a bug but I am unsure where to post it.

When I cast an ability on an enemy, my cursor stays there until it is fully cast. As a consequence, if I cast on something I target forward, if I move my mouth back to move backward or sidewise, the cursor stays blocked in front... so my physical mouse is totally ineffective. I have to wait for the ability to be fully cast before my mouse move can be effective again.

It is particularly annoying in another instance of what I think is the same problem: when I maintain the ability button pressed. Say I want to cast forward any directional ability, I can maintain the button (sometimes, it is even required, for instance when Pantheon wants to throw his Comet Spear [A]). Well, when I do that, I can visualize the direction on my screen. Cool. Personal preference. The problem is that when I maintain the button pushed, I cannot change the direction of the cast anymore before I release the button. So, I cannot adapt to enemy's moves. This is very handicapping.

That used to not be like that for me. It has been like that after some update maybe a couple months ago, not sure. I first did not realize what was happening, thought my connection was spotty or other problems might exist. With time, I have been able pinpoint a little more so that the problem is systematic and does not seem to come from the mouse itself. But, it is very problematic for the gameplay so I decided to inquire here. I have tried to look for some answer online but none of the problems I've read about was like mine. If this behavior is not generalized then it is not a bug so I am unsure where to get help.

Please, let me know if you have faced anything like that. Also, if you are not experiencing such an issue, this is still valuable for me to know.

Thank you in advance, Eager to get more info, hopefully get it fixed and really enjoy playing again.