This isn’t a new feature in Photoshop 2019 but one that is very useful when you want to remove a thin white line around the edge of your image.
1. Select the layer you wish to remove the white edges around your image.
2. Go to Layer then Matting and select Defringe. (Layer > Matting > Defringe)From experience Remove Black Matte or Remove White Matte doesn’t work very well.
3. The Defringe popup dialog box will appear. Adjust the Width pixel according to how much you would like the white edges to be removed and click OK. This is base on your resolution, the large your image the higher the value this number should be [...]