Unfortunately it does not cover form 5471 which is required if you own an interest in a non US company (even if the company is dormant), or form 8858 which many more internationally self employed people now need to fill out as of a few years ago, as most people self employed abroad are now seen by the IRS as a “foreign branch” of a U.S. person.

Is this official? Usually I don’t use government stuff that don’t have a .gov

No, it appears to be run by "OnLine Taxes".

You are not correct, it is a service that is directly linked from the IRS: https://www.irs.gov/e-file-providers/free-file-fillable-form...

It may be made by a contractor but it’s the IRS’ official free filing solution without the sort of income and situation limitations that exist with the free filing products.

That said, I prefer TurboTax’s better competitors like FreeTaxUSA because filling out the forms yourself still really sucks. In the crappy system we have the best you can do is either find a cheap and decent commercial filing solution or get yourself a tax professional, because everything else is a huge time waste.

They certainly link to it, but the TOS says:

These Terms of Service ("Agreement") is a legal agreement between you ("you", "your", "licensee"), and On-Line Taxes, Inc. ("OnLine Taxes", "we", "our" or "us").

That doesn't sounds like the IRS to me. Maybe they do work for the IRS, but it's not them.

Sure but they’re the official completely free filing option where it’s always free even if you don’t qualify for the free tax product that all the other tax services have. It’s not some random fly by night website.

Does it work for Americans aboard that take Foreign Earned Income Exclusion?

Unfortunately it has no support for AMT on Form 1116 (Foreign Tax Credit).

I believe taking any FTC requires doing a full AMT calculation (instructions for schedule 2 line 1) which includes a separate AMT version of 1116, so as far as I know FFF is useless for anyone that takes FTC.