Breaks opening the script editor in Google Sheets

[HarryCutts]

Reproduction steps:

1. Create or open a Google Sheet (at https://docs.google.com/spreadsheets/). (Show the menu bar if it's hidden.)
2. Click Tools > Script editor.

Expected behaviour: the Script editor opens in a new tab. The existing tab should show a vulnerability report.

Actual behaviour: a new tab opens briefly, and the script editor starts loading, but then the new tab closes. A vulnerability report is still shown on the existing tab.

Workaround: click "Ignore this domain in future" on the report screen, then return to the page and try again.