Hi!
It's maybe like this post in C2
https://www.construct.net/en/forum/construct-2/how-do-i-18/rid-black-lines-52246
But I've tried to
1 set the sampling to Nearest.
2 set the pixel rounding
3 set the screenshot to JPG(100)
4 no compress the image when exporting
5 no minify script when exporting
but it still happens!
It's ok when I run in the editor browser!
but it happen when I export and use it in web mobile.
Here is the screenshot taking code
I am trying to take the screenshot and post it in a image elements to let the player save it.