Use https://mozilla.github.io/extension-finder/ it found 1, looked for 2 this is tracking addons being converted and coded for 57 + https://docs.google.com/spreadsheets/d/1TFcEXMcKrwoIAECIVyBU0GPoSmRqZ7A0VBvqeKYVSww/edit#gid=0 as is this http://arewewebextensionsyet.com/#addons can try this also https://alternativeto.net/ Search from here, not always best https://addons.mozilla.org/en-US/firefox/extensions/ for current. Do not need a addon/Extension to do backups. Win7 can, http://www.techradar.com/news/the-best-free-pc-backup-software of 2017 Someone will fill the vacuum, give it time. Just as it took 2wks for tons of code to come out to customize Firefox with usserchrome code. Please let us know if this solved your issue or if need further assistance.

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