More ssb compose fixes.

apps/ssb/tf-compose.js

@@ -342,7 +342,7 @@ class TfComposeElement extends LitElement {
 	remove_mention(id) {
 		let draft = this.get_draft();
 		delete draft.mentions[id];
-		setTimeout(() => this.requestUpdate(), 0);
+		setTimeout(() => this.notify(), 0);
 	}
 
 	render_mention(mention) {
@@ -549,7 +549,7 @@ class TfComposeElement extends LitElement {
 							@input=${this.input}
 							@paste=${this.paste}
 							contenteditable
-							innerText=${live(draft.text)}
+							.innerText=${live(draft.text ?? '')}
 							></span>
 					</div>
 					<div class="w3-half w3-padding">