diff --git a/src/js/scrollback.ts b/src/js/scrollback.ts
index 8d3a054..a934a77 100644
--- a/src/js/scrollback.ts
+++ b/src/js/scrollback.ts
@@ -67,7 +67,7 @@ function processOutput(output: CommandOutput): ["html" | "text", string] {
 
     if (typeof output === "string") {
         content = output
-    } else if (output.html) {
+    } else if (output.html !== undefined) {
         html = true
         content = output.html
     } else {