Type control-shift-A in firefox to bring up the addons manager.
Hit F until you get to the search field.
Enter axe in the search field and hit enter.
After hitting tab a few times you should find:
aXe Developer Tools Thursday, June 14, 2018 Add accessibility auditing to the Firefox Developer Tools More Release Notes: Loading… Install
At this point bring up the contextual menu with either shift-F10 or the Applications key.
The second item should be install. This will then prompt you with a license agreement and a accept and install button.
I believe the rest should be straight forward.
On 6/15/18, 10:12 AM, "firstname.lastname@example.org on behalf of Rob Hudson" <email@example.com on behalf of firstname.lastname@example.org> wrote:
Cohn, Jonathan <email@example.com> wrote:
I have firefox ESR, version 52 something. Where would one find this extention?