diff --git a/src/apps/ssh_app.cpp b/src/apps/ssh_app.cpp
index 349a767..01ed930 100644
--- a/src/apps/ssh_app.cpp
+++ b/src/apps/ssh_app.cpp
@@ -311,7 +311,9 @@ bool SshApp::onKey(const KeyEvent& e) {
 }
 
 void SshApp::update(uint32_t nowMs) {
-    if (!message_.empty() && nowMs - messageMs_ >= kMessageMs) {
+    // nowMs was read before this pass handled its keys: a message a key just set is "later" than it,
+    // and an unsigned difference would call that 49 days old, and clear it at once.
+    if (!message_.empty() && static_cast<int32_t>(nowMs - messageMs_) >= static_cast<int32_t>(kMessageMs)) {
         message_.clear();
         requestRedraw();
     }