Security Researcher Discovers Snippet of CSS Code That Forces iOS to Reboot, Apple Investigating. Monday September 17, 2018 5:23 AM PDT by Mitchel Broussard.

As such, an attacker-crafted email that contains CSS instructions to override the warning snippet's CSS code (display rules) can make the warning disappear altogether: ...

The code snippet of the external CSS and the resulting output for both the in-line style and the paragraph element are displayed in Figure B as viewed in the Chrome browser.