SECURITY REPORT · EXTENSHI SCAN
Inject Custom JS and CSS
Firefox extension·by Iván Ros
0
/ 100 SAFETY SCORE
EXCELLENT
Looks clean. No meaningful risks detected in this scan.
Automated analysis of publicly available code — not a professional security audit. It may produce false positives and does not prove an extension is unsafe or safe. Treat it as one signal among many. Disclaimer · Report an issue
How it ranks
Inject Custom JS and CSS's safety score vs every other extension we've scanned
Globally
90.22%of extensions carry more risk
Riskier ←→ Safer
Ranked across every extension we scan
In its category
80.22%of its category extensions carry more risk
Riskier ←→ Safer
Ranked within its category
Findings
6
median 38Lower is safer
Risky permissions
2
median 1Critical + high perms
Total permissions
5
median 4All declared perms
Critical findings
0
median 2Severity = Critical
Findings breakdown
Automated security signal · 6 findings across 5 severities
6
findings
detected
detected
Critical00%
High117%
Medium350%
Low233%
Info00%
Permissions requested
2 risky permissions of 5 total
1 critical permission require attention
This extension requests 5 permissions in total. 2 of them grant broad capabilities that are worth a careful look.
Critical
Access to all websites
Can read and modify content on every website you visit
High
View open tabs
Can see URLs and titles of all open tabs
Medium
Store local data
Can save data locally in the browser for persistence
Medium
Access current tab
Can temporarily access the content of the active tab when you click the extension
Medium
Monitor navigation
Can observe and track tab navigation events and URL changes
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Scan performed by extenshi.io · Jun 25, 2026· partial run (some scanners failed)
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