Summary

JSS with WebWorker set to Remove break Google spreadsheets. Strict does not break the page in Brave. Unprotected does not break the page in Firefox.

Setup

Pages affected: https://docs.google.com/spreadsheets/d/.... [removed]
JShelter Version: 0.16

0.16 changed WebWorker settings and previous versions in Chromium-based browsers likely worked fine with Recommended.

1. Is JavaScript Shield active? ON
2. Is Network Boundary Shield active? ON
3. Is Fingerprint Detector active? ON
4. What fingerprint likelihood does Fingerprint Detector report? None
5. Did Fingerprint Detector produce any notifications, if so, what was the notification? No
6. JSS level - Recommended

Browser: Tested in Firefox and Brave

How to reproduce

1. Open a spreadsheet
2. The page display an overlay window explaining a problem with a solution that does not fix the issue.
3. In Brave, changing Worker to Remove fixes the issue.
4. In Firefox, changing Worker to Unprotected fixes the issue.

Expected result

The default configuration works smoothly.

Actual result

The user needs to tweak JSS but:

• The solution offered by the page does not work.
• JShelter does not display that WebWorkers are used by the page. See #123 for that issue.
• The solution for Firefox does not prevent Workers from being installed to the browser.

Reproducibility

The issue appears in Brave and Firefox. The issue was originally reported by a user in e-mail.

Workarounds

See above.

Other notes

See also #80