Unfortunately, gimp-app does not give any information whether the gtk build needed to be configured differently. If gimp-app were open source in the sense of the GPL (which it pretends to be but isn't), you could just look at the sources from which it was built and see for yourself.
If you believe something is missing from the package, please e-mail Aaron Voisine and ask him about it.
-- brion vibber (brion @ pobox.com)
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