Jan 21, 2021 If you’re using OS X 10.5.8 Leopard then you can still download Firefox 16 for Macs which works on 10.5.8. However, we strongly recommend you upgrade to at least OS X 10.6 Snow Leopard or higher as Firefox 16 is no longer updated by Mozilla and therefore not secure anymore.
- Since Firefox 17 until the latest version of Firefox, you need at least OS X 10.6 Snow Leopard or higher to run the browser safely and efficiently on your Mac. We emphasize that using Firefox 16 is not a good idea because it is no longer updated or supported by Mozilla leaving it vulnerable to attack, malware, spyware and other online threats.
- Beginning with Firefox 4, Macs must have an Intel x86 processor (which you do NOT have; yours is a PPC Mac) and OSX 10.5 or higher System Requirements: Firefox 4 Firefox 5 Firefox 6 Firefox 7 Firefox 8 The good news is that Firefox 3.6.24 still supports OSX 10.4 and Macs with the PPC Mac architecture.
Firefox version 78 is the last supported Firefox version for Mac users of OS X 10.9 Mavericks, OS X 10.10 Yosemite and OS X 10.11 El Capitan. These users will be moved to the Firefox Extended Support Release (ESR) channel by an application update. This will provide security updates until the next ESR update in July 2021, after which the affected users will no longer receive security updates.
While Apple does not have a public policy governing security updates for older OS X releases, their ongoing practice has been to support the most recent three releases. The last security update applicable to OS X 10.11 was made available in July 2018. Unsupported operating systems do not receive security updates, have known exploits and can be dangerous to use, which makes it difficult to maintain Firefox on those versions.
Up until July 2021, we will be updating affected users with critical security updates through the Firefox ESR channel to help retain the best possible security. After this, no security updates will be provided.
If you want to keep your Firefox version up to date, you will need to upgrade your operating system to macOS 10.12 or higher. Older versions that are not supported by Apple are unreliable and unsafe to use, which also makes it difficult to maintain Firefox on those versions.
Old Firefox For Mac Os X 10.5.8
For more information regarding the removal of Mac OS X 10.5 support look at the bugs below:
[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]
It's been almost six months since Window 2000 and older versions of Windows XP were dropped in Firefox 13 and now Mac OS X 10.5 (aka Leopard) is being de-supported for Firefox 17, starting with its Nightlies, released along with Firefox 14 on 17 July 2012.
10.5 EOL warnings will be given between the next two releases of Firefox (Firefox 15 on 8/28 and Firefox 16 on 10/9) and then a 'no longer supported' notification when Firefox 17 gets released on 20 November 2012. Firefox 16 for which it will be supported until that date will be the final release to support Mac OS X 10.5 and after that 10.5 users will most likely be almost out of options. As Opera will most likely drop 10.5 support before Firefox 10 ESR reaches EOL, switching to TenFourFox with Rosetta is the only viable option.
Furthermore, Mozilla does not even have plans to provide direct support for Extended Support Releases (ESR) to Mac OS X 10.5 users either as the ESR is only for mass-rollout by organisations, which then are on the hook for supporting their users, while Mozilla will only directly support the organisation admins.
Developers have made a final decision that supporting Mac OS X 10.5 would hurt development to provide another year's worth of support for that OS, because developers have to keep around testing infrastructure, Q&A processes for attempting to backport patches to the ESR. Additionally, Firefox 10 ESR will only be supported until 12 February 2013.
Additionally, the cost of keeping 10.5 supported for additional releases (beyond Firefox 16) is simply too high for the benefit received. Because 10.5 marketshare is continuing to shrink at a rapid pace, it will be quite low enough when Firefox 17 is released. Developers still strive to leave code in place for Firefox 17, but if it becomes even difficult to accomplish necessary work, developers may end up breaking things to advance their goals for supported Mac OS versions.
Along with the regular release of Firefox 17, its ESR counterpart will be released as well and will be supported until 3 December 2013 and two releases after Firefox 24 ESR.
More information regarding the removal of Firefox support for Mac OS X 10.5 soon.
Thoughts anyone?