There's a setting on the Firefox desktop version; I guess it's not exposed in the Android version for some reason. These mobile phone browsers tend to be "dumbed-down" in general. Not hard to imagine it just re-uses the same error message from the desktop version, probably just as a simple oversight.

Yeah it's probably an oversight, but that oversight feels particularly irresponsible given that it completely blocks the ability to access web sites (the primary function of a web browser) based on a third-party block list which can't be disabled.

Remember that visited sites are also phoned home to google when the setting is on.

Sure thats true? It would be trivial to just package the whole block list locally.

Last time I checked, which to be fair is a couple years ago now, only a partial hash is shared with google.

They removed about:config from android firefox builds except for the nightly builds. Mildly enraging, that.

I don't know, I got that exact error and searched the settings. I couldn't find that preference either.

maybe the "safe browsing" setting that uses a list from google to block sites (which I always disable)... Mozilla is in bed with Google on so many levels...

On Firefox Android there is no such option displayed in the settings.

It is hidden in about:config, I believe....

That doesn't exist in the Android version.

What good is that? 99.9% or more of users will never visit this page or know what to do with it, much less be able to figure out which knob to toggle.

It's a product design failure to say "blocked because your configuration says so!" and then hide it from settings.

Firefox for Android sucks... but it sucks less then the alternatives, as far as I know

This isn't just Firefox for android. Try visiting a previously HSTS enabled site with a now expired certificate. No option for the user to say "I don't really care that much about the MITM risk, just show me the damned page" even with desktop Firefox. Absolutely mindboggling disrespect for user agency for a so-called user agent.

Mozilla explicitly disables about:config in the stable release of Firefox on Android. Works fine in the beta and nightly releases though.

As for why they disabled it, no clue. Just bitter, disdainful speculation.