An automatic birthday reminder for a dead friend pops up on your phone. It’s a shock. Or worse: you get a Facebook message “from” that friend. They call you on Skype. They message your Gmail account. But it’s only a glitch, or a hacked account. It happens with surprising frequency. Silicon Valley is still catching up with how to secure, close or help pass on social media accounts once their owners die.

It can feel outrageous to consider social media as it relates to death. The former seems so trivial, the latter so momentous. But social media accounts often contain the final vestiges of our self—our face, our interests, our friends, our voice. We work so hard to make our accounts reflect an idealized version of who we are; if we delete them, are we robbing ourselves of our most...