Rated 3 out of 5 stars

Nice addon, but currently it is lacking some privacy features:

There should be a way to clear the cache, for one page individually or globally for all sites.
There should also be the possibility to empty the cache automatically every time the browser closes.

This review is for a previous version of the add-on (0.5.3). 

about clearing the cache

Textarea Cache will not remove the texts saved in the CURRENT session when closing the browser. That is because the browser is sometimes closed accidentally, and the texts should be saved in this case for the user to recover it after restart.\r\n\r\nIf using the default setting, the old saved texts (i.e. texts typed and saved in the previous seesion) will be removed when closing the browser.