feat(gemini): replace file input attachment with clipboard paste for context injection

Author: vchan-in

src/content-scripts/gemini.tsx

@@ -84,33 +84,28 @@ function getConversationId(): string | null {
   return match?.[2] ?? null;
 }
 
-function attachViaFileInput(text: string): boolean {
-  const fileInput = document.querySelector<HTMLInputElement>("input[type='file']");
-  if (!fileInput) return false;
+function injectIntoTextarea(text: string) {
+  const textarea =
+    document.querySelector<HTMLElement>("div[aria-label='Enter a prompt for Gemini']") ||
+    document.querySelector<HTMLElement>(".ql-editor, [contenteditable='true']");
+  if (!textarea) return;
 
   const file = new File([text], "AI_Chat_Backup_Context_Seed.txt", {
     type: "text/plain",
     lastModified: Date.now(),
   });
 
-  const dt = new DataTransfer();
-  dt.items.add(file);
-  fileInput.files = dt.files;
-  fileInput.dispatchEvent(new Event("change", { bubbles: true }));
-  return true;
-}
+  const dataTransfer = new DataTransfer();
+  dataTransfer.items.add(file);
 
-function injectIntoTextarea(text: string) {
-  if (attachViaFileInput(text)) return;
-
-  // File input not yet in DOM – retry for up to 5 s
-  let attempts = 0;
-  const interval = setInterval(() => {
-    attempts++;
-    if (attachViaFileInput(text) || attempts > 20) {
-      clearInterval(interval);
-    }
-  }, 250);
+  const pasteEvent = new ClipboardEvent("paste", {
+    bubbles: true,
+    cancelable: true,
+    clipboardData: dataTransfer,
+  });
+
+  textarea.focus();
+  textarea.dispatchEvent(pasteEvent);
 }
 
 mountWidget(