Be careful!
I had it remove all the images again. That was a Foundation file. And then I was working with a Bootstrap file, and it would not save. I did the same thing three times over, and I dare not open it again to see what I've got now.

.
But I MAY have found a workaround for the not saving. If you have a file that you started on before you updated, save it with a different name first time you do something in the new version. And stick to the new name until you have completed it. Then you may be able to remove the original file that was started earlier, and let the new file have its proper name. I won't swear by this, I'm still testing.
As to this removing the images, try this:
Before you install the new version, make a nonsensical Foundation file, say a wee bit of blurb and a couple of images (the images are important), save it. Then upgrade, (but keep your previous installation file!), and the first thing you open has to be this nonsense file. It will probably open ok, and then you make some changes, add a bit, subtract a bit, change a class name or two, undo some steps, move the slider up, make a change that you delete because you have to do it within the smallest viewport, etc, etc... Just like you would do with a normal file. Then save it over the previous version. MAYBE you are able to trigger this image removal. To me it seems to affect Foundation, and it seems to happen just once (per version, that is

). Just as if there would be some registry key saying 'remove images: run once'.

Again, I can't guarantee that this will do the trick, but I'm testing...