OnOff Shim - 3.3v required or not?

Simple question, but seen some conflicting information. For reasons, I don’t want to use the OnOff Shim as a shim.

Clearly need to connect 5v, Ground, 7 (BCM 4) and 11 (BCM 17). Do I need to connect 3.3v as well?

According to the pinout, its used.

Problem is, that conflicts with the information by a user in one of the comments on the product page itself (https://shop.pimoroni.com/products/onoff-shim) which says:

If you run wires to it, the only connections you need are 5v, Ground, BCM4 and BCM17.

Be interested to know if anyone had practical experience of this…

Leave the 3.3 V unconnected and see if it works? Maybe that commenter got it wrong and it is needed?

For future reference, in case anyone is searching:

OnOff shim works fine with no 3.3v. However, without it connected, you don’t get the led “I am now shutdown” blink

As I’m using an external button, with an inbuilt led, this isn’t an issue - I know that the power is off when the button led turns off.