Security updates will continue, but new innovation will depend on community involvement, the foundation says.
Fans of the popular mail client may want to look elsewhere now that Mozilla is ending development of the product.
The company is pulling back on innovations for the product.
Mozilla confirms details of its Firefox mobile operating system, which it plans to release win 2013 with several partners.
This new feature lets you email large attachments without having to go outside Mozilla's popular mail client.
Also included in Mozilla's new mobile browser are a fresh new look, a more personalized approach, and Flash support.
Mozilla's new silent updater has not sped up the migration to Firefox 13, according to usage statistics compiled by an Irish metrics company.
The update, Flash Player 11.3.300.262, was released Thursday and applies only to Firefox on Windows.
Softly rounded tabs will feature prominently in the browser's upcoming new look.