Flagfox 6.1.x

Flagfox is hosted on Mozilla’s official addon repository, (AMO). You can always download the latest version of Flagfox from here:

Flagfox information & screenshots
Flagfox downloads & changelog

Flagfox 6.1+ supports Firefox 60+ (ESR). The full browser support history table is available here.

Flagfox 5.2.x

Mozilla no longer permits “legacy” XUL/XPCOM API addons and now mandates all addons be written using their newer (and worse) WebExtension API. Flagfox 6.0+ is required for Firefox 57+ support, however whilst Firefox 52 ESR is still (somewhat) supported by Mozilla, Flagfox 6.0+ cannot support it due to fundamental technical limitations. As such, Flagfox 5.2.x ESR updates are being provided here for the remainder of the Firefox 52 ESR life-cycle, which ends in August 2018. Firefox forks based on this are also supported, however extensive fork-specific support is not provided (e.g. if something is broken vs. Firefox, report it to your fork).

Installation Requirements:
Flagfox 5.2.x ESR requires Firefox 52 ESR, including updates, or a fork based on at least that version, and will not run in later versions of Firefox. Running one of these versions also unfortunately requires disabling of Mozilla’s addon signing requirements, which you can easily do by setting the “xpinstall.signatures.required” preference to false in about:config. Automatic updates are also not available, however upgrading to Firefox 57+ will allow for automatic update to Flagfox 6.0+. Hashes are provided below for integrity checking, if desired.

Flagfox 5.2.x ESR files can be downloaded here:

Download Flagfox 5.2.11
  SHA2-256 hash of 5.2.11: 87255649f4b274018407a47d6a151e26867b02194a9dddb35f92a4c5c84a359d
Download Flagfox 5.2.10
  SHA2-256 hash of 5.2.10: d882170e4a968670f86a56f28b66d47f98718804ff29b64c66c398e04bd8d0a8
Download Flagfox 5.2.9
  SHA2-256 hash of 5.2.9: 754aa7473e4d2fe7910bc94731cd3f72ec377a0a9d5a407238cec83e344952ee
Download Flagfox 5.2.8
  SHA2-256 hash of 5.2.8: 8a53da52e4a53a893cf3a1411b7ba6c664d2d4cacc6346cb76fc72f5bd35b0ac
Download Flagfox 5.2.7
  SHA2-256 hash of 5.2.7: b82fe908fcd79d23bcc9c7c62e36f283afb4c9c9ae22e5cf5c01631d0fa51fd8
Download Flagfox 5.2.6
  SHA2-256 hash of 5.2.6: 5842d56636fae15a1ff2e22d6244572195ffc76542aeed43b892396fee21b4d7
Download Flagfox 5.2.5
  SHA2-256 hash of 5.2.5: d9a65af06dc5ef28dd7387f0407de12e018a75c222c2cc0464c31522cd535f11
Download Flagfox 5.2.4
  SHA2-256 hash of 5.2.4: a8bc496c9bc70650c17378c71f9379f13cb0f4a1795d74fd706dbbac9e0ff5ea

Flagfox 5.2.3 was the last version of Flagfox 5.2.x signed by and hosted on AMO, which you can download here:

Download Flagfox 5.2.3

Note: Installation of Flagfox 5.2.x is required to migrate Flagfox options and custom actions from prior versions of Flagfox into the format/API also used in Flagfox 6.0+. (more info)