It’s been 3 weeks since Mozilla released Firefox 115 ESR.
How long do folks at Tor project take to update their browser to FF new releases?
115 seems like an important one, it brings isolation to 3rd-party iframes, GPU isolation and some exploit protection for the Windows browser.
The current Firefox ESR is still 102. Firefox 115 ESR is available as an opt-in, but most people on the ESR channel will not be upgraded until 115.2 is released next month. Even the current latest download on their site downloads 102.
The release calendar @brivacy linked doesn’t show Tor Browser 13 being released until September 13. ESR 102 will still be supported until this time, so it seems fine.
I don’t know about these specific things, but in general it’s also important to remember that many security/privacy hardening features are developed in Tor Browser first and then upstreamed to Firefox, so relying solely on comparing version numbers does not always paint the full picture. Tor Browser also disables many Firefox features by default which mitigates a lot of vulnerabilities, making a lot of Firefox security patches less critical (because in many cases the feature being patched does not even apply to Tor Browser).