Top Risks

• THREAT FEED: extension ID independently confirmed malicious by TPCI chrome-mal-ids — HTML validator + malext.io malicious_extension_sentry (+2.5, capped).
• Uninstall URL hijack hook present — unusual for a developer tool, raises monetization/tracking concern.
• Install URL hijack opens third-party page on install.
• Privacy policy is Google's generic policy (unscoped, admits 3rd-party sharing) — not extension-specific.
• No developer name; weak accountability for an extension with external host references.

Evidence

• uninstall_url_hijack crx chrome.runtime.setUninstallURL() present; target null but hook fires — webstore signal +3.0.
• install_url_hijack crx onInstalled opens https://htmlvalidator.app/welcome — third-party URL redirect on install.
• generic_privacy_policy store Policy URL is Google account policy (scope_extension=false, data_collection=true, third_party_sharing=true) → +10.0 privacy.
• no_developer_name store developer_name is empty string — no 'Offered by' accountability signal.
• maintenance_stale store 21 months since last update (12-24mo band) → maintenance pillar +6.0.
• dom_sink_innerhtml crx ace.js uses innerHTML from variable; no CSP present — elevated XSS risk → code quality +2.0.
• no_csp manifest content_security_policy is null; MV3 has strict defaults but csp_present=false noted.
• js_external_hosts crx Extension references example.com, github.com, htmlvalidator.app as external JS hosts.
• threat_feed_membership api Extension ID listed by TPCI chrome-mal-ids — HTML validator + malext.io malicious_extension_sentry; score 5.15 -> 7.65 (+2.5 cap 2.5).

Permissions Breakdown

• storage low Local extension storage only; no host access granted.

Pillar Scores

Bookkeeping