TWI in slave mode using port PF2 and PF3

I need to use the ATmega4809 with I2C configured in slave mode using pins PF2 and PF3.
The only way to obtain that is to add:

`PORTMUX.TWISPIROUTEA |= TWI_MUX;`
`TWI0.DUALCTRL = TWI_ENABLE_bm;`

after the `Wire.begin(4);`

Probably the instruction: `PORTMUX.TWISPIROUTEA |= TWI_MUX` is missing inside the function TWI_SlaveInit() in file twi.c

Those who have more experience than me can check.

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