More screen reader accessibility fixes.

static/skald.js

@@ -435,10 +435,10 @@ function setConnected(connected) {
         for(let elt of document.querySelectorAll('.connected-only')) {
             if(connected) {
                 elt.classList.remove('invisible');
-                elt.removeAttribute('aria-hidden');
+                setAccessibleHidden(elt, false);
             } else {
                 elt.classList.add('invisible');
-                elt.setAttribute('aria-hidden', 'true');
+                setAccessibleHidden(elt, true);
             }
         }
     }
@@ -2200,6 +2200,12 @@ function gotFileTransfer(f) {
     div.classList.add('message-row');
     let box = document.getElementById('box');
     box.appendChild(div);
+    if(!f.up) {
+        announceChat(
+            `File offer from ${f.username}: ${f.name}. ` +
+            'Choosing Accept will disclose your IP address.',
+        );
+    }
     return div;
 }
 
@@ -3620,6 +3626,7 @@ document.getElementById('resizer').addEventListener('keydown', function(e) {
 function displayError(message, level) {
     if(!level)
         level = "error";
+    let text = String(message);
     let position = 'center';
     let gravity = 'top';
 
@@ -3635,9 +3642,14 @@ function displayError(message, level) {
         break;
     }
 
+    if(level === "info")
+        announceChat(text);
+    else
+        announceUrgent(text);
+
     /** @ts-ignore */
     Toastify({
-        text: message,
+        text: text,
         duration: 8000,  // Increased from 4000 for screen reader users
         close: true,
         position: position,
@@ -3742,6 +3754,13 @@ function toggleLeftPanel() {
     );
 }
 
+function setChatPanelVisible(visible) {
+    let chatPanel = document.getElementById('left');
+    setVisibility('left', visible);
+    if(chatPanel)
+        setAccessibleHidden(chatPanel, !visible);
+}
+
 document.getElementById('sidebarCollapse').onclick = function(e) {
     e.preventDefault();
     toggleLeftPanel();
@@ -3762,7 +3781,7 @@ document.getElementById('closeside').onclick = function(e) {
 
 document.getElementById('close-chat').onclick = function(e) {
     e.preventDefault();
-    setVisibility('left', false);
+    setChatPanelVisible(false);
     setVisibility('show-chat', true);
     resizePeers();
     document.getElementById('show-chat').focus();
@@ -3770,7 +3789,7 @@ document.getElementById('close-chat').onclick = function(e) {
 
 document.getElementById('show-chat').onclick = function(e) {
     e.preventDefault();
-    setVisibility('left', true);
+    setChatPanelVisible(true);
     setVisibility('show-chat', false);
     resizePeers();
     document.getElementById('close-chat').focus();
@@ -3891,7 +3910,7 @@ document.addEventListener('keydown', function(e) {
 
         if(isChatVisible) {
             // Collapse chat
-            setVisibility('left', false);
+            setChatPanelVisible(false);
             setVisibility('show-chat', true);
             resizePeers();
 
@@ -3909,7 +3928,7 @@ document.addEventListener('keydown', function(e) {
             }, 100);
         } else {
             // Expand chat
-            setVisibility('left', true);
+            setChatPanelVisible(true);
             setVisibility('show-chat', false);
             resizePeers();