Though Firefox browser doesn’t have in-built Sandboxing option but it has certain add-on/extensions which can help and act quite like sandbox technology, the best among them is Multi-Account Containers develop by Mozilla.
Normally while browsing through Firefox browser when we click the + button lying to the right of the current tab in Firefox, a new tab opens with a pristine browsing session.
But after installing Multi-Account Containers extensions when we click the + button it displays the menu of currently available containers.
When clicked on the menu it gives default options of personal, work, banking and shopping. These options can be deleted, modified or renamed. Even new containers can be added to the menu. When a website opens in a particular container and reopen it in the same container it will have a pristine start, having no old cookies and any cookies that are set will only be accessed using that particular container.