Do not show button if clipboard not available

assets/css/main.css

@@ -27,4 +27,8 @@ pre {
 
 .fail {
     color: #800000;
-}
+}
+
+.hidden {
+    display: none;
+}

assets/js/copyclipboard.js

@@ -1,5 +1,6 @@
 "use strict";
 
+const COPY_TO_CLIPBOARD_CONTAINER_ID = "copyToClipboardContainer";
 const COPY_TO_CLIPBOARD_STATUS_ID = "copyToClipboardStatus";
 let copyToClipboardCtr = 0;
 
@@ -13,7 +14,9 @@ function copyToClipboardSuccess() {
 function copyToClipboardFail(cause) {
     let statusElem = document.getElementById(COPY_TO_CLIPBOARD_STATUS_ID);
     if (!cause) cause = "unknown error";
-    statusElem.innerText = "copy failed: " + cause;
+    let msg = "copy failed: " + cause;
+    console.log(msg);
+    statusElem.innerText = msg;
     statusElem.classList.remove("success");
     statusElem.classList.add("fail");
 }
@@ -22,11 +25,7 @@ function copyToClipboard(url) {
     let copyEventIdx = ++copyToClipboardCtr;
 
     if (!window.navigator.clipboard) {
-        let msg = "could not access clipboard";
-        if (window.location.protocol !== "https:") {
-            msg += ": website not using HTTPS"
-        }
-        copyToClipboardFail(msg);
+        copyToClipboardFail("could not access clipboard");
         return;
     }
     window.navigator.clipboard.writeText(url).then(() => {
@@ -37,3 +36,16 @@ function copyToClipboard(url) {
         copyToClipboardFail();
     });
 }
+
+(function () {
+    if (!window.navigator.clipboard) {
+        let msg = "cannot access clipboard";
+        if (window.location.protocol !== "https:") {
+            msg += ": website not using https"
+        }
+        console.error(msg);
+    } else {
+        let container = document.getElementById(COPY_TO_CLIPBOARD_CONTAINER_ID);
+        container.classList.remove("hidden");
+    }
+})();

assets/templates/html/pasteMeta.html.tmpl

@@ -7,7 +7,7 @@
 {{end}}
 
 {{define "body"}}
-<pre>
+<pre id="copyToClipboardContainer" class="hidden">
 <button onclick="copyToClipboard('{{.RootURL}}/{{.Paste.Key}}{{.FileExt}}')">Copy URL to clipboard</button> <span id="copyToClipboardStatus"></span>
 </pre>
 <pre>