I am making a very simple scene, the scene only contains Camera, EventSystem, Canvas, there is a Button under Canvas, Button is full of Canvas，Buttons can be clicked under the editor, all fields can be。After packaging the exe，My monitor resolution is 4K (38401080), open the exe and set the resolution to 25601080，There are some areas on the right that cannot be clicked, about 20%，Then set the program resolution to 38401080, all areas can be clicked。Next, I set a custom resolution with the graphics card, set it to 25601080, and set the display resolution to 25601080. After opening the program, you can also click in all areas.The version of unity I am using is Unity2021.3.8f1c1 and Unity2022.1.13f1c1。When I was at a loss, I installed unity2020.3.18f1c1. After packaging, the resolution was set to 25601080, and all areas could be clicked.
I have found the cause of the problem，The picture is the GraphicRaycaster script comparison between unity 2021.3.8 and unity 2020.3.18 UGUI
Yeah the latest 2021.3.6+ versions have broken raycasters or at least changed how they worked enough old UIs don’t work.
There’s many threads complaining about this.