diff --git a/parser/htmlparser/metrics.yaml b/parser/htmlparser/metrics.yaml
new file mode 100644
index 000000000000..7ee44acfed23
--- /dev/null
+++ b/parser/htmlparser/metrics.yaml
@@ -0,0 +1,64 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Adding a new metric? We have docs for that!
+# https://firefox-source-docs.mozilla.org/toolkit/components/glean/user/new_definitions_file.html
+
+---
+$schema: moz://mozilla.org/schemas/glean/metrics/2-0-0
+$tags:
+  - 'Core :: XML'
+
+ysod:
+  shown_ysod:
+    type: event
+    description: >
+      This event is recorded only for Firefox UI documents (chrome).
+      Recorded when a Yellow Screen of Death is shown. The `value` is a
+      url on which the error happened. Yellow Screen of Death happens when
+      XML or XHTML document encounters a parsing error. It is commonly a
+      result of the document being malformed or missing DTD entity.
+      This data should be reviewed periodically for urls that error frequently.
+      This event was generated to correspond to the Legacy Telemetry event
+      ysod.shown#ysod.
+    bugs: &ysod_shown_bugs
+      - https://bugzil.la/1657242
+    data_reviews: &ysod_shown_data_reviews
+      - https://bugzil.la/1657242
+    notification_emails:
+      - gtatum@mozilla.com
+      - nordzilla@mozilla.com
+      - earo@mozilla.com
+      - vchin@mozilla.com
+    expires: never
+    extra_keys:
+      value:
+        description: >
+          The url of the Firefox UI (chrome) document that showed the YSOD.
+        type: string
+      error_code:
+        description: >
+          Code of the XML Error (See `XML_Error` enum in expat.h for the list of errors where XML_ERROR_NONE is 0).
+        type: quantity
+      location:
+        description: >
+          Location as Row:Column of where the error happened.
+        type: string
+      last_line:
+        description: >
+          The content of the last line that led to the error.
+        type: string
+      last_line_len:
+        description: >
+          The length of the last line that led to the error.
+        type: quantity
+      hidden:
+        description: >
+          The document is hidden.
+        type: boolean
+      destroyed:
+        description: >
+          The container of this document is destroyed.
+        type: string
+    telemetry_mirror: Ysod_Shown_Ysod
diff --git a/parser/htmlparser/nsExpatDriver.cpp b/parser/htmlparser/nsExpatDriver.cpp
index 0719ea9c5893..f522ffad5262 100644
--- a/parser/htmlparser/nsExpatDriver.cpp
+++ b/parser/htmlparser/nsExpatDriver.cpp
@@ -35,7 +35,7 @@
 #include "mozilla/IntegerTypeTraits.h"
 #include "mozilla/NullPrincipal.h"
 #include "mozilla/Telemetry.h"
-#include "mozilla/TelemetryComms.h"
+#include "mozilla/glean/GleanMetrics.h"
 
 #include "nsThreadUtils.h"
 #include "mozilla/ClearOnShutdown.h"
@@ -1108,30 +1108,19 @@ nsresult nsExpatDriver::HandleError() {
       docShellDestroyed.Assign(destroyed ? "true"_ns : "false"_ns);
     }
 
-    mozilla::Maybe<nsTArray<mozilla::Telemetry::EventExtraEntry>> extra =
-        mozilla::Some<nsTArray<mozilla::Telemetry::EventExtraEntry>>({
-            mozilla::Telemetry::EventExtraEntry{"error_code"_ns,
-                                                nsPrintfCString("%u", code)},
-            mozilla::Telemetry::EventExtraEntry{
-                "location"_ns,
-                nsPrintfCString(
-                    "%lu:%lu",
-                    lineNumber.unverified_safe_because(RLBOX_SAFE_PRINT),
-                    colNumber.unverified_safe_because(RLBOX_SAFE_PRINT))},
-            mozilla::Telemetry::EventExtraEntry{
-                "last_line"_ns, NS_ConvertUTF16toUTF8(mLastLine)},
-            mozilla::Telemetry::EventExtraEntry{
-                "last_line_len"_ns, nsPrintfCString("%zu", mLastLine.Length())},
-            mozilla::Telemetry::EventExtraEntry{
-                "hidden"_ns, doc->Hidden() ? "true"_ns : "false"_ns},
-            mozilla::Telemetry::EventExtraEntry{"destroyed"_ns,
-                                                docShellDestroyed},
-        });
-
     mozilla::Telemetry::SetEventRecordingEnabled("ysod"_ns, true);
-    mozilla::Telemetry::RecordEvent(
-        mozilla::Telemetry::EventID::Ysod_Shown_Ysod, mozilla::Some(path),
-        extra);
+    mozilla::glean::ysod::ShownYsodExtra extra = {
+        .destroyed = mozilla::Some(docShellDestroyed),
+        .errorCode = mozilla::Some(code),
+        .hidden = mozilla::Some(doc->Hidden()),
+        .lastLine = mozilla::Some(NS_ConvertUTF16toUTF8(mLastLine)),
+        .lastLineLen = mozilla::Some(mLastLine.Length()),
+        .location = mozilla::Some(nsPrintfCString(
+            "%lu:%lu", lineNumber.unverified_safe_because(RLBOX_SAFE_PRINT),
+            colNumber.unverified_safe_because(RLBOX_SAFE_PRINT))),
+        .value = mozilla::Some(path),
+    };
+    mozilla::glean::ysod::shown_ysod.Record(mozilla::Some(extra));
   }
 
   // Try to create and initialize the script error.
diff --git a/toolkit/components/glean/metrics_index.py b/toolkit/components/glean/metrics_index.py
index 82cc19b80dcd..7f79e282e791 100644
--- a/toolkit/components/glean/metrics_index.py
+++ b/toolkit/components/glean/metrics_index.py
@@ -40,6 +40,7 @@ gecko_metrics = [
     "netwerk/metrics.yaml",
     "netwerk/protocol/http/metrics.yaml",
     "parser/html/metrics.yaml",
+    "parser/htmlparser/metrics.yaml",
     "security/certverifier/metrics.yaml",
     "security/manager/ssl/metrics.yaml",
     "services/common/metrics.yaml",