@craigraw In Sparrow, when spending from the Postmix UTXOs why do the change land back into the Postmix UTXOs? Shouldn't the change be considered doxxic and be moved to the Badbank? 

To my understanding, the change in the Postmix UTXOs will not be remixed, so a merchant, who you just paid and who knows who you are, could follow your change and where you spend it to down the line..

Am I missing something?

Thank you for your excellent work on Sparrow btw. 

 There is certainly an argument for this  - it really depends on whether the change is really doxxic or not.