Hi Carl, yours is the first new report I've seen of this. That problem isn't expected to repeat for a couple more years when the current certificate expires. Here's one way to check whether Firefox is very confused about what year it is:

Open Firefox's Web Console using either:

• "3-bar" menu button > Web Developer > Web Console
• (menu bar) Tools > Web Developer > Web Console
• (Linux/Windows) Ctrl+Shift+k

In the command line area, which may be either a single line starting with >> or a large rectangular area, type

Date()

and press Enter or if you see one, click the Run button. Does Firefox display a sensible date?

There were problems with my system clock, as a matter of fact. So, how can I convince Firefox to check that again? Restart it? Cumbersome, because i have many, many tabs open, but possible.

There's a 24-hour delay, so before quitting and restarting, clear this timestamp:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

(2) In the search box in the page, type or paste xpi- and pause while the list is filtered

(3) Find the app.update.lastUpdateTime.xpi-signature-verification preference and click the trash can at the right end of the bar.

After the restart, it will probably be a few minutes before Firefox runs the re-verification.

I have the same issue, but for my websites. They used to be fine, and they are suddenly marked insecure. Most of them have no options for input from users anyhow, so what's insecure about that?

http://savingcommunities.org

Hi pimann, can you copy/paste the error code that looks like SEC_ERROR_SOME_DETAILS into a reply here? Sometimes the code is immediately visible and in other cases, you need to click the Advanced button.