Release Notes for v39.8.9

Other Changes

• Fixed gn gen failing to resolve electron_version when building from a git worktree checkout. #51163 ^{(Also in 40, 41, 42)}
• Security: backported fixes for CVE-2026-6296, CVE-2026-6297, CVE-2026-6298, CVE-2026-6299, CVE-2026-6300, CVE-2026-6301, CVE-2026-6302, CVE-2026-6303, CVE-2026-6304, CVE-2026-6305, CVE-2026-6306, CVE-2026-6307, CVE-2026-6308, CVE-2026-6309, CVE-2026-6311, CVE-2026-6312, CVE-2026-6313, CVE-2026-6314, CVE-2026-6316, CVE-2026-6318, CVE-2026-6358, CVE-2026-6359, CVE-2026-6360, CVE-2026-6361, CVE-2026-6362, CVE-2026-6363, CVE-2026-6364. #51141