On 28 January 2021, the tax office of the Canton of Zurich announced that from the 2020 tax period onwards, the online tax return (incl. enclosures) for natural persons can be submitted with ZHprivateTax without a signature and without a release receipt.
Those who complete their tax return offline using the downloaded "Private Tax" software must still print it out, sign it and submit it on paper.
The full communication is available here.