If creating a wrap around image, and using the blur filter, or creating a blur layer, visible seams appear where the image wraps around. There doesn't seem to be an option to tell the filter to consider the image edge as "wrapped".

The same probably applies to all filters that rely on convolution.

Reproducible: Always

Steps to Reproduce:
1. Create a new image
2. Turn on wrap around mode using W
3. Draw a few strokes
4. Add a blur filter layer
5. Zoom into the edge of the image

Actual Results:  
Seams appear near the edges of the image

Expected Results:  
Image should remain smooth across wrapping border.