Google plus plugin for firefox browser is also available on Mozilla Add-ons, you can download google plus and access google plus social network account directly on the browser.Google plus extension have been created to access all the features of google plus social network directly from your web-browser.
The add-ons for google plus for browsers are tested and are running without any issues. You can download free plugins for google plus directly from chrome shop and mozilla add-ons without spending a single percent.
Google Plus firfox extension will not affect speed of web browser. They are tend to only connect you with your social circles 24 hours a day.