> Update Tor Browser to 7.0 (based on Firefox 52 ESR) which is multiprocess and paves the way to content sandboxing. This should make it harder to exploit security vulnerabilities in the browser.
Firefox 52 ESR sounds like mainline Firefox to me.
Literally the same version of Firefox as underpins Tor Browser will tend, pretty much at all times, to be safer than Tor Browser. You can use the search bar at the bottom of the page to find out why, or search the Internet for "grugq tor browser" if you want more people explaining the issue.
> Literally the same version of Firefox as underpins Tor Browser will tend, pretty much at all times, to be safer than Tor Browser.
This is absolutely false. Especially if you're considering the alpha versions which include Selfrando.
See "Real-world Exploits against the Tor Browser" pages 9-10 where they conclude,
> The reason is that these function pointers are only accessed through an indirection layer, i.e., memory objects on the heap contain a pointer to a virtual table which is located in the code or data section of the application and contains a number of pointers to virtual functions. Since the attackers can only disclose the virtual table pointer, but not the virtual table itself, as it is not on the heap, they cannot disclose gadget addresses. Note that, when only ASLR is applied, the address of the virtual table is randomized with the same offset as the ROP gadgets. Therefore, such an attack can bypass ASLR but not selfrando.
> We therefore conclude that selfrando can thwart most real-world exploits. Attackers can only succeed in rare cases where they can disclose the complete heap and data section.
> Update Tor Browser to 7.0 (based on Firefox 52 ESR) which is multiprocess and paves the way to content sandboxing. This should make it harder to exploit security vulnerabilities in the browser.
Firefox 52 ESR sounds like mainline Firefox to me.