diff --git a/resources/extensions/EventLogging.jsonSchema.less b/resources/extensions/EventLogging.jsonSchema.less
new file mode 100644
index 0000000..be66426
--- /dev/null
+++ b/resources/extensions/EventLogging.jsonSchema.less
@@ -0,0 +1,4 @@
+/* Define z-index property to ensure proper stacking, thus fixing T249557 */
+.mw-json-schema-code-samples {
+	z-index: 1;
+}
diff --git a/skin.json b/skin.json
index 96b8dec..150c57e 100644
--- a/skin.json
+++ b/skin.json
@@ -97,6 +97,7 @@
 		"timeless": {
 			"+oojs-ui-core.styles": "resources/ooui.less",
 			"+ext.echo.styles.badge": "resources/extensions/Echo.less",
+			"+ext.eventLogging.jsonSchema.styles": "resources/extensions/EventLogging.jsonSchema.less",
 			"+ext.visualEditor.core": "resources/extensions/VisualEditor.core.less",
 			"+ext.visualEditor.desktopArticleTarget.noscript": "resources/extensions/VisualEditor.article.less",
 			"+ext.CodeMirror.visualEditor.init": "resources/extensions/VisualEditor.CodeMirror.less",