Why is the PIC16F1619 DAC1OUT on a Curiosity board always at 0 V in debug mode?

The PIC16F1619's pin 19 is mapped both PGD and DAC1OUT. In debug mode, the ICSP pins (PGD and PGC) are activated to communicate with the debugger. In debug mode, these pins cannot be used by the application code and, with the exception of communication events, pin 19 reads 0 V.
To view the voltages on DAC1OUT, program the board in production mode and use a scope on pin 19.

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