Make get_focus_text and set_focus_text support Telegram Web's input widget.

core/js/get_focus_text.js

@@ -5,6 +5,10 @@
     if (activeElement && inputs.indexOf(activeElement.tagName.toLowerCase()) !== -1) {
         return activeElement.value;
     } else {
-        return undefined;
+        if (window.location.href.startsWith("https://web.telegram.org/") && activeElement.hasAttribute("placeholder")) {
+            return activeElement.textContent;
+        } else {
+            return undefined;
+        }
     }
 })();

core/js/set_focus_text.js

@@ -1,7 +1,12 @@
 (function() {
     let newText = "%1";
     const activeElement = document.activeElement;
-    activeElement.value = decodeURIComponent(escape(window.atob(newText)));
+
+    if (window.location.href.startsWith("https://web.telegram.org/")) {
+        activeElement.textContent = decodeURIComponent(escape(window.atob(newText)));
+    } else {
+        activeElement.value = decodeURIComponent(escape(window.atob(newText)));
+    }
 
     // Note: simulate input event on active element after set focus text.
     // Some website need input event before submit form.