Zhenyi Tan And a Dinosaur

Dismissed Share Extensions (Can) Still Run in the Background

There’s a weird bug in Time Capsule: when you’re in the middle of saving a web page, sometimes you can tap “Cancel” and still get the output HTML.

Actually… this behavior seems useful! If I can reliably reproduce this, I can then dramatically cut down the saving time and let the users get back to their browsing sooner. Unfortunately, no one on the internet is talking about this. Apple’s documentation is also unhelpful: “Tells the host app to cancel the app extension request.”

So to test it out, I created a simple app: the main app shows a number and a reset button, the share extension increment the number while running. I ran it, and here’s what happened:

Nice. It seems like the extension continues to run even after being dismissed.

I’m a bit tempted to add an “It’s now safe to close this popup” label in the extension UI, but as long as the behavior remains undocumented, it’s too risky.

So if you tried it and it works for you, great! But keep this between you and me, OK?