Hi @RobertB4444, that's definitely incorrect. See this explainer from TurboTax mentioned above and Publication 555 from the IRS. From Page 10 of that IRS publication, under the heading "Separate Return Preparation": "Form 8958 is also used for registered domestic partners who are domiciled in Nevada, Washington, or California. A registered domestic partner in Nevada, Washington, or California must follow state community property laws and report half the combined community income of the individual and his or her registered domestic partner."
The FAQ you posted also includes Q13:
Q13. How should registered domestic partners report wages, other income items, and deductions on their federal income tax returns?
A13. Registered domestic partners should report wages, other income items, and deductions according to the instructions to Form 1040, U.S. Individual Income Tax Return, and related schedules, and Form 8958, Allocation of Tax Amounts Between Certain Individuals in Community Property States. Form 8958 is used to determine the allocation of tax amounts between registered domestic partners. Each partner must complete and attach Form 8958 to his or her Form 1040.
