The use of recursiveApplyNodes, introduced in ca0d473b as part of the refactor that enabled the rest of the input modes, missed a significant subtlety of the layer enumeration: recursiveApplyNodes works top-down, while G'MIC expects layers to be sorted bottom-up.
Build Krita, no update to G'MIC is necessary. Stack two images. Run G'MIC, select Stylize filter, and check that the image on top is the style, and gets applied to the bottom. Check that the image is applied on return in the bottom layer.
@davidrevoy -- as the only docs I have on this are the GIMP host code, could you please throw all you have at this and check I've not introduced any other bugs? Especially as regards layer position on return from G'MIC.
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