Latest Adobe release includes their version of Resynthesizer plugin. Videos at YouTube.
It seems to me that we need to persuade the Gimp project to include Resynthesizer in their distribution. The fact that the company whose name is mud has a Resynthesizer is not a compelling argument, but helps.
If Gimp included Resynthesizer, then the site that distributes the MS Windows port of Gimp would include Resynthesizer. The fact that including the Resynthesizer would help Windows users is also not a compelling argument.
Possibly, Gimp doesn't include Resynthesizer because it has some weaknesses: I have experimented with some improvements to Resynthesizer. One improvement is to make Resynthesizer fill the selection (the target of the fill) starting near the context (near the edge of the selection.) Currently, the resynthesizer fills the target randomly, without any ordering by nearness to the context. (For example, just by chance it might start filling the selection at the center, where there is no nearby context to make the fill match the context.) Whether to order fill by nearness to the context could be an option. Ordering fill by nearness to the context sometimes leads to undesired artifacts in the fill, but usually leads to a better result. Ordering fill by nearness to context still uses some randomness, otherwise undesirable artifacts are likely.
This helps the Uncrop plugin work better. Also, it might help the case where you have rotated an image and want to fill in the resulting wedges at the corners (a popular tutorial, for which many users resort to Filter/Map/Resynthesizer instead of Filter/Enhance/Heal Selection exactly because they want to force Resynthesizer to use a certain context near the target. And it might help the case where you are stitching together a panorama and want to fill in missing chunks at the edge instead of cropping them out. And it helps the case where the context is not homogenous, for example with a horizon extending across the target selection.
The package that Gimp should include contains:
Heal selection plugin (the fixed version)
Smart enlarge plugin (possibly renamed?)
A plugin to fill missing chunks at the edge of the image (named ?)
Other plugins to simplify the other uses of the Resynthesizer plugin e.g. texture mapping?