PEOPLE WHO HAVE TO RENAME FILES HATE HIM!
It's possible other people might have discovered this before, but I discovered it today and wanted to share.
.smod files are just renamed .zip files, as we all know. But unlike .zip files, you can’t directly open them in the file browser if you want to look through them, or at least I couldn’t, by default. Until now, I got by with either opening them in 7zip or copying their contents out to a regular folder. But we can do better! (If we have administrator privileges, at least.)
Run the command prompt as an administrator. (For me, the easiest way is to go to the start menu, type “cmd”, right click on the entry that says “Command Prompt” and click “Run as administrator”.) Type the following command and then Enter.
assoc .smod=CompressedFolder
You can close the command prompt after that. When you next open ...\Stonehearth\mods, any .smod files should appear with a zipped folder icon and you can look inside, though it may be a bit slow, and if you’re doing anything serious an unzipped copy might still be a good idea. But if you just want to look at a couple files… this might save some time.