Modal Dialog don't work normally after new Pega version updated
Dear Pega support,
I have trouble with Modal Dialog.
In my old version (8.3/ 8.4), I have a location action to display a modal dialog. I set this override pzModalTemplate of Pega and I set my template's name as "ErrDialog". It normally works until I update the Pega version to 8.7.
The height of Modal "ErrDialog" be shorter than before and a scroller appears although I don't change anything.
This problem is like below.

I've fixed it already, but I don't know why it happened.
Could anyone explain this to me more clearly?
Thank you.
***Edited by Moderator Marije to add Capability tags***
@TienDTT1
Try to check the skin rule modification in area of modal dialog. Try to update the style of modal dialog according to your requirement and update the same in the local action setting which you might have applied on button.