When in Pattern Preview mode, a Gaussian Blur will normally work across the image seams to give a smoothly tiling seamless result. However I have found that if the Blur is done as part of an Action, that it will act as if Pattern Preview were not on.
This happens even if the Action was recorded with Pattern Preview on, and also even if turning on Pattern Preview is a previous recorded step in the Action.
Steps to Reproduce:
1. With any image open, use View> Pattern Preview to see it tile.
2. Start recording a new Action
3. Use Filter > Blur > Gaussian Blur
4. See that it blurs seamless, which is correct.
5. Stop recording your Action.
6. Undo all changes to the image.
7. With Pattern Preview still active, play the new Action.
8. See that there are seams on this blur.
Bug seen in Photoshop version 25.3.1, on Windows
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