Whenever scratchpad content is saved it opens a connection to https://sb-ssl.google.com/.

Edit:
The issue turned out like this. From the extensions source code one sees that "Save" button functions as download. It triggers google safebrowsing. Removing all of the safe browsing settings from about:config fixes it. User introduced about:config changes are not permanent. For reasons unknown they revert to default values. Accordingly extensions using such save require an advisory about privacy.