I've been editing several iterations of a photo with 9 layers and noticed something funny after I deleted two of the layers—the file size actually became much larger instead of decreasing in size as I expected. The file was 225MB at first and then grew to ~290MB after deleting the two layers and saving the file. That's the only change I made. I edited three other versions of this image and they all experienced the exact same issue.
These files are being saved on a network drive, so versions are not supported. I'm running OS X El Capitan 10.11.4 and the latest version of PIxelmator 3.6. I'm editing 16 bit PXM files.
Any ideas? Has anyone else experienced this?