Support for Firefox ESR releases

Does Duo support the use of the Firefox ESR releases? ESR: Extended Support Release – like a “Long Term Release”, it’s officially supported and distributed by Mozilla.

The current one (60.7.1esr) is being flagged by Duo Web as being old, but was released today (2019/06/18). (The authentication log entry for that Access says the browser was “Firefox 60.0”.)

This pops up periodically. Per this thread on the Mozilla forums, Mozilla “stopped putting minor version numbers in the user agent string after Firefox 10”. This is problematic for Extended Support Release (ESR) detection, because the user’s browser no longer publishes enough information to allow Duo to reliably determine whether the browser is a fully-patched ESR version.

I believe this has been fixed in previous ESR versions. It may be addressed in the one you’re referencing.

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Found that “window.navigator.buildID” can be used to determine if a version of Firefox is ESR (one would need a list): info from

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