identity.launchWebAuthFlow() headaches

[thdoan]

Currently my extension uses identity.getAuthToken() to handle authorization. This works fine in Chrome -- I've stayed logged in for the entire day (so far), but the same cannot be said for Edge and Firefox. These two browsers only support  identity.launchWebAuthFlow(), which requires me to save the access token to local storage and reuse it until it expires. The problem is the access token expires after an hour or so, which requires the user to log in again -- not a good UX for an extension.

Is there a way to get identity.launchWebAuthFlow() working similar to identity.getAuthToken(), where the user is not asked to log in again every hour?