When I apply Warp transformation, the changes go unsaved - neither in the xfs nor exported_as_jpg will show any of the transformations, and after saving/exporting the picture is back to “before” dimensions in the Gimp.
What am I up against? How can I win?
I use the Warp tool (“Tools/Transform tools/Warp transform”) fairly often. It’s very easy to make a lot of changes on a layer and then for example switch to a new layer, at which point all the changes are lost.
If something like this is what’s happening in your case, the solution is to make your changes on a given layer, then hit the Enter key before you do anything else. This “commits” the changes you just made. Otherwise, sometimes (but not always, depending on exactly what the next thing you do actually is) those changes are lost.
There’s an open bug report on this issue:
If none of this sounds like what’s happening in your case, then the next questions would be what operating system, what version of GIMP, what exact steps, etc.
Gimp 2.10.4 under Linux (xubuntu)
now after @Elle 's comment (hit Enter) I’ve found that you need one more operation after Warp and you can export everything correctly. If I apply warp followed by dodge and burn, everything is saved/exported correctly.
This warp transform bug has been fixed in 2.10 from git. So for the next release of GIMP 2.10, this bug won’t be a problem. Also another issue with warp transform (changing layers loses work) has also been fixed and the fix will be in the next release of GIMP 2.10 - yeah! this other bug has cost me a lot of lost time.
Hello, I have GIMP 2.10.6 and I’m running into this same problem.
I make changes using the warp tool and then as soon as I click save the changes disappear.
Is there anything I can do about this?
As already noted, you really do have to hit “return” when you are done using the Warp tool. So let’s say you select a layer, select the Warp tool, use the Warp tool to make several transforms in a row. When you are done using the Warp tool, leave the cursor hovered over the image (can be tricky if you are usinga tablet). Then hit the return key. If you have the history dialog open, at that point you should see “Warp transform” or something similar appear in the history dialog. Then you should be able to save the xcf file, except that @beachbum seems to suggest that first you need to select another tool such as dodge/burn, then hit Save.
Try this and see if it works. If not, please describe what actually happened.
Just a minor note: the fix applies to all transformation tools, not just Warp Transform. And yes, upgrading to 2.10.8 strongly recommended 
Ah didn’t realize you had to hit Enter to commit changes!
That seems to have done it.
Thanks!