Open drain usage with internal pullups

As far as I know, the weak pull-up value is identical to value of i/o pin pull-up resistor before and during configuration documented in table 5-3 of DC characteristics, that is 10 to 50 k for LVTTL. I use it e. g. for static inputs as configuration switches, but slow dynamic operation would be also possible. Susceptibility to capacitive coupled interferences should be considered, howevewer.