Firefox ESR for ubuntu ppa install by terminal تثبيت فيرفكس إصدار دعم موسع على أوبنتو
Mozilla will offer an Extended Support Release (ESR) based on a
regular release of Firefox for desktop for use by organizations
including schools, universities, businesses and others who need extended
support for mass deployments.
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sudo add-apt-repository ppa:mozillateam/ppa
sudo apt-get update
sudo apt-get install firefox-esr
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