It may be a little different depending on the version, but basically in the Image Menu click on Canvas Size.
From there, you can modify the width of the image canvas to add the 10 pixels. Make sure that the new width and heights first match the original, as the dialog tends to keep the last values you use.
Then just use the arrows to position the image so the ten pix are applied to the right side.
You want to increase the width by 10 px, keeping the height as it is.
Then Using the positioning arrows set it so the image is kept to the left, so lick in the arrow pointing straight to the left.
Then use the background square to select the color for the line.
Then click o.k and you get your 10 pix line.
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Phil AKA Vacunita
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Ignorance is not necessarily Bliss, case in point:
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