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edit: I might have misread the problem but the image posted, while it has an alpha channel also is completely solid - just green shapes and the black. I will attach that houston4.png made with black BG.
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What you have done there is take the advice too literally and added a solid black layer. Exporting as a png and the image is flattened and the layer then becomes part of the png.
The background (BG) color does come into it. The set BG color is used for the alpha mask used by applications to denote transparency. Some games etc might work best with black rather than the more usual white.
You can determine the colour used with applications such as ImageMagick but all you really need to know is
Does the transparency show in gimp (that checker pattern)
Is the BG set to black.
example - the two versions.
![[Image: beEDkBD.jpg]](https://i.imgur.com/beEDkBD.jpg)
My advice, do not try and fix it, start again
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edit: I might have misread the problem but the image posted, while it has an alpha channel also is completely solid - just green shapes and the black. I will attach that houston4.png made with black BG.
----------
What you have done there is take the advice too literally and added a solid black layer. Exporting as a png and the image is flattened and the layer then becomes part of the png.
The background (BG) color does come into it. The set BG color is used for the alpha mask used by applications to denote transparency. Some games etc might work best with black rather than the more usual white.
You can determine the colour used with applications such as ImageMagick but all you really need to know is
Does the transparency show in gimp (that checker pattern)
Is the BG set to black.
example - the two versions.
My advice, do not try and fix it, start again