Imported images have black borders that don't respond to croping either with area tool or brush tool. I can only get rid of them if i use another layer to cover the line. The line disappears and reappears depending on the zoom level and on the size of the image. Some of these lines are visible after rendering while others arent.
a little follow up - i can eliminate some of the lines that otherwise appear after rendering if i play around with the downsample amount setting and canvas size. When i set the downsample amount to draft and then scale up the image and then change the downsample to best, some of the lines disappear and also dont show up during rendering.
Thank you. I've also been dealing with this issue and I have been searching and searching for a solution. Also Merry Christmas
Your source image, the "?" is of pretty low resolution and shows many compression artifacts. Using higher resolution alpha images in psd format should eliminate the "lines" which appear to be artifacts.