SECURITY REPORT · EXTENSHI SCAN
FireCSS
Firefox extension·by derivia
How it ranks
FireCSS's safety score vs every other extension we've scanned
Globally
99%of extensions carry more risk
Riskier ←→ Safer
Ranked across every extension we scan
In its category
90%of its category extensions carry more risk
Riskier ←→ Safer
Ranked within its category
Findings
0
median 38Lower is safer
Risky permissions
3
median 1Critical + high perms
Total permissions
4
median 4All declared perms
Critical findings
0
median 2Severity = Critical
Findings breakdown
Automated security signal · 0 findings across 5 severities
0
findings
detected
detected
Critical00%
High00%
Medium00%
Low00%
Info00%
Permissions requested
3 risky permissions of 4 total
1 critical permission require attention
This extension requests 4 permissions in total. 3 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
High
Observe web requests
Can monitor all network requests made by the browser
Medium
Store local data
Can save data locally in the browser for persistence
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Scan performed by extenshi.io · Jun 25, 2026· partial run (some scanners failed)
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