Site Inaccessible in Firefox

"Content Encoding Error

The page you are trying to view cannot be shown because it uses an invalid or unsupported form of compression.

*Please contact the website owners to inform them of this problem."

Weird though…

CCleaner + CCEnhancer. Tick everything.

It’s a really old problem and common.
Some solutions over at FF site:
https://support.mozilla.org/en-US/questions/945251

Clearing the cache manually helped one user.

Earlier me and Zaralyth had a related issue. Upon visiting forums.ffshrine.org I was redirected to an error page mentioning those two things:

– https://support.mozilla.org/en-US/kb/what-does-your-connection-is-not-secure-mean#w_the-certificate-is-not-trusted-because-it-is-self-signed
– https://support.mozilla.org/en-US/kb/what-does-your-connection-is-not-secure-mean#w_the-certificate-is-only-valid-for-site-name (given URL was: snowwhite.ffshrine.org)

At first, we’ve been told by Jessie that it was down for a bit, but Sarah fixed it. Then, the issue came back again after a while, among a bunch of Database Errors (for me, at least)… Sarah is working on it.

I got HTTPS Everywhere installed as an add-on in FF. So that might be also why I get the error sometimes, too.
I just refresh the site after a couple seconds to get the site loaded.