Templates still not saving in doc builder

I seem to remember a post recently saying saving issues with doc builder have been fixed, but I still cannot save templates.
When I click 'Save', the green banner appears to confirm the save, the page appears to refresh, but when I navigate to Templates there's nothing there.
Have tried the usual; log out/in, clear cache/cookies. Not a naming issue, have tried unique/gibberish names to test.

Edit: also noticed that nothing happens once a preview is generated. Click Preview, align client to the preview, OK, green banner says it's generating and then nothing.