1 files changed, 5 insertions, 1 deletions
diff --git a/app/ui.js b/app/ui.js
index ff0f176..c277eea 100644
--- a/app/ui.js
+++ b/app/ui.js
@@ -1049,6 +1049,7 @@ const UI = {
         UI.rfb.addEventListener("serververification", UI.serverVerify);
         UI.rfb.addEventListener("credentialsrequired", UI.credentials);
         UI.rfb.addEventListener("securityfailure", UI.securityFailed);
+        UI.rfb.addEventListener("clippingviewport", UI.updateViewDrag);
         UI.rfb.addEventListener("capabilities", UI.updatePowerButton);
         UI.rfb.addEventListener("clipboard", UI.clipboardReceive);
         UI.rfb.addEventListener("bell", UI.bell);
@@ -1362,7 +1363,8 @@ const UI = {
 
         const viewDragButton = document.getElementById('noVNC_view_drag_button');
 
-        if (!UI.rfb.clipViewport && UI.rfb.dragViewport) {
+        if ((!UI.rfb.clipViewport || !UI.rfb.clippingViewport) &&
+            UI.rfb.dragViewport) {
             // We are no longer clipping the viewport. Make sure
             // viewport drag isn't active when it can't be used.
             UI.rfb.dragViewport = false;
@@ -1379,6 +1381,8 @@ const UI = {
         } else {
             viewDragButton.classList.add("noVNC_hidden");
         }
+
+        viewDragButton.disabled = !UI.rfb.clippingViewport;
     },
 
 /* ------^-------