diff --git a/patches/extra/ungoogled-chromium/enable-certificate-transparency-and-add-flag.patch b/patches/extra/ungoogled-chromium/enable-certificate-transparency-and-add-flag.patch
new file mode 100644
index 00000000..26409ebd
--- /dev/null
+++ b/patches/extra/ungoogled-chromium/enable-certificate-transparency-and-add-flag.patch
@@ -0,0 +1,22 @@
+--- a/chrome/browser/browser_features.cc
++++ b/chrome/browser/browser_features.cc
+@@ -50,7 +50,7 @@ BASE_FEATURE(kBookmarkTriggerForPrerender2,
+ // switch.
+ BASE_FEATURE(kCertificateTransparencyAskBeforeEnabling,
+              "CertificateTransparencyAskBeforeEnabling",
+-#if BUILDFLAG(GOOGLE_CHROME_BRANDING)
++#if true
+              base::FEATURE_ENABLED_BY_DEFAULT);
+ #else
+              base::FEATURE_DISABLED_BY_DEFAULT);
+--- a/chrome/browser/ungoogled_flag_entries.h
++++ b/chrome/browser/ungoogled_flag_entries.h
+@@ -140,4 +140,8 @@
+      "Spoof WebGL Info",
+      "Return generic values for WebGLDebugRendererInfo to remove a potential data leak while preventing potential website breakage. ungoogled-chromium flag.",
+      kOsAll, FEATURE_VALUE_TYPE(blink::features::kSpoofWebGLInfo)},
++    {"enforce-certificate-transparency",
++     "Enforce Certificate Transparency",
++     "Enforce Certificate Transparency for certificates that sites present. This is enabled by default. ungoogled-chromium flag.",
++     kOsAll, FEATURE_VALUE_TYPE(features::kCertificateTransparencyAskBeforeEnabling)},
+ #endif  // CHROME_BROWSER_UNGOOGLED_FLAG_ENTRIES_H_
diff --git a/patches/series b/patches/series
index b4ab9b23..dc0f4ec7 100644
--- a/patches/series
+++ b/patches/series
@@ -110,3 +110,4 @@ extra/ungoogled-chromium/enable-extra-locales.patch
 extra/ungoogled-chromium/disable-chromelabs.patch
 extra/ungoogled-chromium/remove-pac-size-limit.patch
 extra/ungoogled-chromium/add-flag-to-spoof-webgl-renderer-info.patch
+extra/ungoogled-chromium/enable-certificate-transparency-and-add-flag.patch