My application work in android and ios and no related problem until I updated a new version using updated editor which is 2019.4 。
It is very strange that when I open my application in IOS, It is no any problem,
But after I switched to another application and then go back to my application, Some images and text colour become pale. Some transparent part of image become not transparent.
Please advise.
please help.
Attached the video .
anyone help?
The debug console in XCode do not show any error when switching the application, But the images in screen become wired.
Hmmm that’s unfortunate 
Is it possible for you to switch back to the previous version, and does everything work as expected then? If so, then I’d definitely file a bug report with a repro-case for this, sounds like something regressed …
Hopefully it’s something we can quickly uncover, but please be aware that the 2019 LTS version is nearing the end of its support cycle (see https://unity.com/releases/2019-lts)