Mozilla Firefox gradually and bit by bit adding more highlights to improve online security and protection. As a piece of its bigger undertaking called "tor elevate", the "letterboxing" strategy was obtained from Tor and made a piece of Mozilla Firefox for its refresh due in mid-May 2019.
It's sort of convoluted and difficult to see, however you should know it really is great for protection. It is the expansion of dark spaces to the sides of your program when you resize it. To numerous individuals, this would appear to be peculiar yet the principal explanation for this is to keep sponsors from following your perusing conduct. These promoters utilize the mix of your program screen goals and working framework rendition to make a one of a kind ID, with letterboxing they can't follow you.
Letterboxing gives you a chance to increment or decline the program window (or augmenting/going to full screen) while including dim spaces around the substance you're seeing.
At the point when the client expands the window, the biggest conceivable viewport is utilized, again a variety of 200 x 100. Void dark edges in the chrome some portion of the window spread whatever is left of the screen. Likewise, in full screen, the viewport is again given measurements a numerous of 200 x 100, and the chrome regions around it are set to dark.
Along these lines, yours and a million other individual's program goals remain the equivalent and following you isn't as simple. This is an enemy of fingerprinting strategy which keeps promoters from following your perusing movement. Firefox as of now has another enemy of fingerprinting strategies included too.
Be that as it may, the missing component is a notice that reveals to you what the outcomes can be of augmenting your program. This tells publicists what your screen's size is. In view of Mozilla's representative's remark, they don't anticipate including this component in Firefox at any point in the near future. Letterboxing isn't turned on of course and should be chosen from the program's security settings.