SecurityError: The operation is insecure

[BirkhoffLee]

This issue was raised in #11, but my users have encountered this issue on iPad Safari too, so I figured I'd submit another issue in here.

User agent: Mozilla/5.0 (iPad; CPU OS 12_5_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.2 Mobile/15E148 Safari/604.1

Stack trace:

Error: SecurityError: The operation is insecure.
  at ? (/client.js:1:2109)

I'm not sure how to reproduce this issue.