I don’t think highlighting the disagreement between “leftists” and “liberals” is very clarifying here. That kind of clarification tells me “liberals are leftists except for the differences highlighted,” but the differences highlighted seem to be everything that makes a leftist a leftist.
Google tells me that liberal means socially progressive (i.e. culturally left) and promoting social welfare.
How does your definition differ?
Please don’t tell me it’s just “they’re not always progressive and don’t always promote welfare.” : )