![Filezilla for osx 10.6 Filezilla for osx 10.6](/uploads/1/2/5/6/125632734/349609650.png)
Leopard-webkit - a build of WebKit for 10.5 Leopard and 10.6 Snow Leopard. So it's pretty much Safari. TenFOURfox - a build of Firefox (Gecko engine) for 10.4 and 10.5. Both are still being updated regularly, at the time of writing. I'll continue to update this post as time goes on.
I don't think that there are any browser versions for 10.6.8 that are fully supported anymore (Safari, Chrome, or Firefox). There are browser versions for OS 10.8 (two OS versions newer than 10.6)that are no longer fully supported. Your MacBook 4,1 is from 2008and unfortunately the maximum OS for it is 10.7.5.
You really need at least OS 10.9 (Mavericks) to get a browser version that is fully supported at this moment (July, 2016). But as mentioneda MacBook 4,1 cannot run OS 10.9. For what it's worthI have a perfectly working Mac Plus from 1986and there are no fully supported browsers for it either.
Having a fully functioning computer (regardless of age)unfortunately is not a prerequisite for being being useful or compatible forever & ever. Eventually older hardware becomes obsoleteeven if it does still work perfectly.
HTH, - Nick p.s. Just in case you meant MacBook Pro 4,1 (and not a MacBook 4,1). A MacBook Pro 4,1 can run the latest OS version (10.11 El Capitan). And if this is the computer you actually haveyou could upgrade the OS & get newer fully compatible browser versions.
The direct answer to the question, from a Macbook 4.1 user, is Chrome. The 'no longer supported' means very little unless you experience major crashes, or require assistance. I beaver away happily with OS 10.6.8 and Chrome on both Macbook and Mini, but do not use Safari because it has security flaws that are no longer fixed by Apple because. The OS is no longer 'supported'. Camino is a lightweight, but fast, FFox.
There is also iCab, which is fast, but quirky, and you need to buy the full version if you want it to run ad-free, and finally Opera (about which I have strong misgivings).
Since Mozilla is ending its support for Firefox for Mac OS X 10.6.8 through 10.8.5 by the end of this August, how are you going to continue Waterfox support for these OS X versions, since it seems that Waterfox's core comes from the Mozilla group, directly, and I see your current version of Waterfox for Mac is exactly the same as Mozilla Firefox. So, my question is, is Waterfox, also, ending its support for OS X 10.6-10.8, as well, since Mozilla will longer create source code to support these older OS X versions? I do not know why Waterfox's developer hasn't replied to my query, but I have a strong, sneaking suspicion that the developer relies heavily on Mozilla's own coding and since Mozilla just ended support for OS X 10.6-10.8 with their last full feature version of Firefox (version 48.0), I have a feeling we older OS X users will NOT be seeing anymore Waterfox upgrades/updates for OS X 10.6-10.8 from this developer, any longer. Waterfox's last version for OS X 10.7-10.8, is the same version number as Mozilla Firefox. So, that tell me this version of Waterfox maybe done and the last version for older OS X users. Mozilla is continuing secuirty versions of an older (version 45) through their Firefox ESR program which will only offer security updates only for versions 45-50 until April 2017. No new browser feature updates.
The Firefox ESR extension program is targeted to Enterprise and educational institutions, but individuals CAN ignore this and download and install the Firefox ESR versions that, will still run on OS X 10.6-10.8. You just won't get any new features and newer add-ons and extensions may not be compatible with this ESR version of Mozilla Firefox. Download and install Firefox ESR here. I kept both versions of FF on my system and labelled the ESR version Firefox ESR to differentiate the last full version of FF for OS X 10.6-10.8 and the security updates only version. The only other supported web browser for OS X 10.6-10.8 is SeaMonkey Check them out!