OK, at https://support.1password.com/v3-extension-firefox/ you suggest using Firefox ESR 38 in lieu of FF 40 and above. However, this sentence could do with clarification: "It will give you time to consider the other two options below before Mozilla also removes the widget module in May 2016, according to their ESR schedule."
Looking at the schedule, https://www.mozilla.org/en-US/firefox/organizations/faq/ FF ESR 38.8.x will be the last version to support 1Pwd3 and will be superseded by FF ESR 45.2.0. While the latter will NOT support 1Pwd3, as long as a user does not go past FF ESR 38.8.x they should still be able to use 1Pwd3. The widget module will be removed from ESR releases starting with ESR 45.0 in March 2016 as I read the schedule. Do you know if Mozilla plans on removing the module from ESR 38.8 in May 2016? AFAIK, they just don't plan on any security updates after 31 May 16.
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