Mozilla plans to add a new security feature to Firefox 82 that will prevent files from downloading automatically under certain conditions.
The feature will block downloads starting from sandboxed iframes, a technology used by websites and services to display content such as ads or multimedia on third-party websites.
Sandboxed iframes are not usually used to start downloads, but most browsers do not block these downloads.
From Firefox 82 onwards, automatic downloads from sandboxed iframes will be blocked by the Firefox browser. Developers can configure "allow-download" to allow these downloads.
Depending on the setting, downloads may be automatically saved in the system download folder, but Firefox can be configured to display "save to" each time a download starts in your browser. This prompt provides an extra level of protection against unwanted downloads, as you can press the cancel button to stop the download before it reaches the system.
How do you set it up? Open the about: preferences # general internal address in the Firefox address bar, and look down at the downloads section. The setting must be set to "Always ask you where to save files". This setting may not be convenient for you, as a message will appear every time you download a file, but it offers more security.
Firefox 82 will be released on October 20, 2020 according to Mozilla program. The next stable release is Firefox 81 which will be released in September 2020.