CVE-2026-8970: constrain AsyncPrefs by remoteType so a compromised content
process cannot set security-relevant prefs via AsyncPrefs; split the
allowlist into privileged-about and unprivileged-exposed sets (Bug 2032174)
CVE-2026-8961: add locationspecific="true" to Thunderbird's PopupAutoComplete
panel so the form-autocomplete dropdown is dismissed on navigation, closing a
spoofing window (Bug 1962625)