Is Greasemonkey Safe?
Greasemonkey — Nerq Trust Score 55.0/100 (C grade). Score based on 2 independent trust signals. Last analyzed: 2026-04-12
Greasemonkey is a Firefox extension with a Nerq Trust Score of 55.0/100 (C), based on 3 independent data dimensions. Last analyzed: 2026-04-12 Security: 90/100. Popularity: 45/100. Data sourced from addons.mozilla.org metadata, permissions analysis, and source code availability. Last updated: 2026-04-12. Machine-readable data (JSON).
Is Greasemonkey safe?
Trust Score Breakdown — Greasemonkey has a Nerq Trust Score of 55.0/100 (C). Measured across 2 independent trust signals (as of 2026-04-12).
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.
What is Greasemonkey and who maintains it?
| Author | Anthony Lieuallen |
| Category | Firefox Add-ons |
| Source | N/A |
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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-on
When evaluating any Firefox add-on, watch for: excessive permissions, data harvesting.
Measured Signals
Greasemonkey has a Nerq Trust Score of 55/100 (C). This score is a composite of automated measurements of security, maintenance, community, and quality signals.
Key Takeaways
- Greasemonkey has a Trust Score of 55/100 (C).
- The score is a measured composite — it is not a suitability judgment. Evaluate the individual signals against your own requirements.
- Query the current measured values via the Nerq API.
Detailed Score Analysis
| Dimension | Score |
|---|---|
| Security | 90/100 |
| Maintenance | 50/100 |
| Popularity | 45/100 |
| Quality | 40/100 |
| Community | 35/100 |
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 (0-100, higher = fewer measured security issues).
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), maintenance (50/100), popularity (45/100), quality (40/100), community (35/100). 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.
Signals last measured on April 12, 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 measurements based on publicly available signals. They are not endorsements, verdicts, or guarantees of suitability. Always evaluate the signals against your own requirements.