This page lists privacy policies for the Chrome extensions that I have published.
Extensions that do not collect any data are not listed here.
You may specify a StackExchange ID (and optionally use StackExchange's mechanism to grant an StackExchange API token) to enable the extension to function. This data is stored locally only, and only used with the StackExchange API to receive notifications for inbox messages. No other data is collected, and the data is not used for any other purpose.