Is Greasemonkey Safe?
Greasemonkey — Nerq Trust Score 55.0/100 (C grade). Based on analysis of 2 trust dimensions, it is has notable safety concerns. Last updated: 2026-04-01.
Use Greasemonkey with some caution. Greasemonkey is a Firefox add-on with a Nerq Trust Score of 55.0/100 (C), based on 3 independent data dimensions. It is below the recommended threshold of 70. Security: 90/100. Popularity: 45/100. Data sourced from addons.mozilla.org metadata, permissions analysis, and source code availability. Last updated: 2026-04-01. Machine-readable data (JSON).
Is Greasemonkey safe?
CAUTION — Greasemonkey has a Nerq Trust Score of 55.0/100 (C). It has moderate trust signals but shows some areas of concern that warrant attention. Suitable for development use — review security and maintenance signals before production deployment.
What is Greasemonkey's trust score?
Greasemonkey has a Nerq Trust Score of 55.0/100, earning a C grade. This score is based on 2 independently measured dimensions including security, maintenance, and community adoption.
What are the key security findings for Greasemonkey?
Greasemonkey's strongest signal is security at 90/100. No known vulnerabilities have been detected. It has not yet reached the Nerq Verified threshold of 70+.
What is Greasemonkey and who maintains it?
| Author | Anthony Lieuallen |
| Category | firefox |
| Source | N/A |
Similar Firefox by Trust Score
Safety Guide: Greasemonkey
What is Greasemonkey?
Greasemonkey is a Firefox add-on — Customize the way a web page displays or behaves, by using small bits of JavaScript..
How to Verify Safety
Review permissions on addons.mozilla.org. Check if source code is available.
You can also check the trust score via API: GET /v1/preflight?target=Greasemonkey
Key Safety Concerns for Firefox add-ons
When evaluating any Firefox add-on, watch for: excessive permissions, data harvesting.
Trust Assessment
Greasemonkey has a Nerq Trust Score of 55/100 (C) and has not yet reached Nerq trust threshold (70+). This score is based on automated analysis of security, maintenance, community, and quality signals.
Key Takeaways
- Greasemonkey has a Trust Score of 55/100 (C).
- Review carefully before use — below trust threshold.
- Always verify independently using the Nerq API.
Detailed Score Analysis
| Dimension | Score |
|---|---|
| Security | 90/100 |
| Privacy | 90/100 |
| Reliability | 50/100 |
| Transparency | 60/100 |
| Maintenance | 60/100 |
Based on 5 dimensions. Data from addons.mozilla.org metadata, permissions analysis, and source code availability.
What data does Greasemonkey collect?
Greasemonkey has a privacy score of 90/100. Review the documentation and privacy policy for data handling details.
Full analysis: Greasemonkey Privacy Report · Privacy review
Is Greasemonkey secure?
Security score: 90/100. This meets the recommended security threshold for production use.
Nerq monitors this entity against NVD, OSV.dev, and registry-specific vulnerability databases for ongoing security assessment.
Full analysis: Greasemonkey Security Report
How we calculated this score
Greasemonkey's trust score of 55.0/100 (C) is computed from addons.mozilla.org metadata, permissions analysis, and source code availability. The score reflects 5 independent dimensions: security (90/100), privacy (90/100), reliability (50/100), transparency (60/100), maintenance (60/100). Each dimension is weighted equally to produce the composite trust score.
Nerq analyzes over 7.5 million entities across 26 registries using the same methodology, enabling direct cross-entity comparison. Scores are updated continuously as new data becomes available.
This page was last reviewed on April 01, 2026. Data version: 1.0.
Full methodology documentation · Machine-readable data (JSON API)
Frequently Asked Questions
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Disclaimer: Nerq trust scores are automated assessments based on publicly available signals. They are not endorsements or guarantees. Always conduct your own due diligence.