Firefox-60.6.1: add-ons removed, cannot re-install
 

Yesterday (2019-05-04) all my firefox-60.6.1 add-ons were removed and trying to re-install them failed. This URL explained the problem: <https://discourse.mozilla.org/t/certificate-issue-causing-add-ons-to-be-disabled-or-fail-to-install/39047>, but my installation has the option, "Allow firefox to install and run studies" disabled. In fact all three options to allow firefox to collect and use data are not available.

Re-installing 60.6.1 makes no difference.

Is there a fix for this?

Found the solution: change the firefox configuration of xpinstall.signatures.required to false.

Or just update to Firefox 60.6.2esr, which has just been released for -current