EHTip installed from addons.mozilla.org could not be verified

Add-ons
1

Hi,

In Firefox 48, I have installed EHTip from https://addons.mozilla.org/en-US/firefox/addon/ehtip/, which is supposed to be signed, as per Add-on signing in Firefox | Firefox Help,

Add-ons installed through the official Firefox Add-ons site go through security checks before they are published. These add-ons are verified and signed. When you install an add-on through another website, Firefox checks to make sure that the add-on is digitally signed.

it should have been checked.

When I install it, after first restart it works, but next restart disables it with:

EHTip could not be verified for use in Firefox and has been disabled.

Any idea how can I continue using this add-on?

2

Have you uninstall firefox and install again?

3

No, but I have removed add-on, restarted FF and installed add-on.
Do you think uninstalling and installing FF again, but using the same “old” profile would make any difference?

4

I have uninstalled FF and reinstalled with clean profile, installed EHTip from official site and still the same error.
This is happening on Arch. However, FF on Mint shows that it can’t be verified, but says “Proceed with caution”. Both are FF 48.

5

I think the problem that it is enabled on first restart only, and later not, is because this addon generates sqlite db inside its directory on first run, so it can’t be verified on later runs because dir content has changed.

Can someone confirm that?

6

Yes, if the add-on is unpacked and changes its own installation directory, the signature verification will fail the next time Firefox starts.