SECURITY REPORT · EXTENSHI SCAN
Custom 404 Page Notifier
Firefox extension·by MB66
How it ranks
Custom 404 Page Notifier'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
1
median 1Critical + high perms
Total permissions
2
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
1 risky permission of 2 total
1 high-risk permission require attention
This extension requests 2 permissions in total. 1 of them grant broad capabilities that are worth a careful look.
High
View open tabs
Can see URLs and titles of all open tabs
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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