fix composer issue and more

src/tests/send-message.js

@@ -18,8 +18,12 @@ const assert = require('assert');
 
 module.exports = async function sendMessage(session, message) {
   session.log.step(`writes "${message}" in room`);
-  const composer = await session.waitAndQuery('.mx_MessageComposer');
+  // this selector needs to be the element that has contenteditable=true,
+  // not any if its parents, otherwise it behaves flaky at best.
+  const composer = await session.waitAndQuery('.mx_MessageComposer_editor');
   await composer.type(message);
+  const text = await session.innerText(composer);
+  assert.equal(text.trim(), message.trim());
   await composer.press("Enter");
   session.log.done();
 }