diff --git a/app/src/js/scrollback.ts b/app/src/js/scrollback.ts
index b465a6d..bdcb9f4 100644
--- a/app/src/js/scrollback.ts
+++ b/app/src/js/scrollback.ts
@@ -111,7 +111,7 @@ function processOutput(output: CommandOutput): ["html" | "text", string] {
         content = output
     } else if (Array.isArray(output)) {
         content = output.join(" ")
-    } else if (output.html !== undefined) {
+    } else if ("html" in output) {
         html = true
         content = output.html
     } else {