ES2020 Operators support

[Fee0]

I would like to have support for the operators coming with ES2020 (https://www.w3schools.com/jS/js_2020.asp):

• The Nullish Coalescing Operator (??)
• The Optional Chaining Operator (?.)
• Logical AND Assignment Operator (&&=)
• Logical OR Assignment (||=)
• Nullish Coalescing Assignment (??=)

Any hints how to implement them are very welcome. I probably start with the Logical AND / OR as these seem more simple to me.