Pasting an image from out of jspaint ignores transparent selection

[naufik]

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Reproducing

1. Use the select tool set selection mode to transparent selection.
2. Set secondary color to, say, white.
3. Paste an image from an external source (not from within jspaint itself) that has contains the secondary color.
4. Verify that selection mode is still transparent selection.
5. Without deselecting the image, move the pasted image - then the white (for this example) color will not be rendered as transparent. This can be fixed by selecting opaque selection and then setting it back to transparent selection.

Expected Behavior

Either:

• the secondary color in the pasted image is rendered as transparent, or
• the selection type is opaque when the image is pasted