diff --git a/plugins/base/public/message.html b/plugins/base/public/message.html
index cfb0169..343f79e 100644
--- a/plugins/base/public/message.html
+++ b/plugins/base/public/message.html
@@ -115,7 +115,8 @@
 	{{if .IsHTML}}
 		<!-- TODO: add a src fallback -->
 		<!-- allow-same-origin is required to resize the frame with its content -->
-		<iframe id="email-frame" srcdoc="{{.Body}}" sandbox="allow-same-origin"></iframe>
+		<!-- allow-popups is required for target="_blank" links -->
+		<iframe id="email-frame" srcdoc="{{.Body}}" sandbox="allow-same-origin allow-popups"></iframe>
 	{{else}}
 		<pre>{{.Body}}</pre>
 	{{end}}
diff --git a/plugins/base/routes.go b/plugins/base/routes.go
index 7b02f11..a5c6c21 100644
--- a/plugins/base/routes.go
+++ b/plugins/base/routes.go
@@ -250,6 +250,7 @@ func handleGetPart(ctx *koushin.Context, raw bool) error {
 		// TODO: be more strict
 		p.AllowElements("style")
 		p.AllowAttrs("style")
+		p.AddTargetBlankToFullyQualifiedLinks(true)
 		body = p.Sanitize(body)
 		isHTML = true
 	}