keybindings: fix error on alt+h

Fixes the following JS error:

    TypeError: e.setReceipt is not a function

components/app.js

@@ -16,7 +16,7 @@ import ScrollManager from "./scroll-manager.js";
 import Dialog from "./dialog.js";
 import { html, Component, createRef } from "../lib/index.js";
 import { strip as stripANSI } from "../lib/ansi.js";
-import { SERVER_BUFFER, BufferType, ReceiptType, ServerStatus, Unread, State, getServerName, isMessageBeforeReceipt } from "../state.js";
+import { SERVER_BUFFER, BufferType, ReceiptType, ServerStatus, Unread, State, getServerName, receiptFromMessage, isMessageBeforeReceipt } from "../state.js";
 import commands from "../commands.js";
 import { setup as setupKeybindings } from "../keybindings.js";
 import * as store from "../store.js";
@@ -133,16 +133,6 @@ function showNotification(title, options) {
 	}
 }
 
-function receiptFromMessage(msg) {
-	// At this point all messages are supposed to have a time tag.
-	// App.addMessage ensures this is the case even if the server doesn't
-	// support server-time.
-	if (!msg.tags.time) {
-		throw new Error("Missing time message tag");
-	}
-	return { time: msg.tags.time };
-}
-
 function getReceipt(stored, type) {
 	if (!stored || !stored.receipts) {
 		return null;

keybindings.js

@@ -1,4 +1,4 @@
-import { ReceiptType, Unread, BufferType, SERVER_BUFFER } from "./state.js";
+import { ReceiptType, Unread, BufferType, SERVER_BUFFER, receiptFromMessage } from "./state.js";
 
 function getSiblingBuffer(buffers, bufID, delta) {
 	let bufList = Array.from(buffers.values());
@@ -19,22 +19,24 @@ export const keybindings = [
 			app.setState((state) => {
 				let buffers = new Map();
 				state.buffers.forEach((buf) => {
-					if (buf.messages.length > 0) {
-						let lastMsg = buf.messages[buf.messages.length - 1];
-						app.setReceipt(buf.name, ReceiptType.READ, lastMsg);
-					}
-
 					buffers.set(buf.id, {
 						...buf,
 						unread: Unread.NONE,
 						prevReadReceipt: null,
 					});
 
+					let receipts = {};
+					if (buf.messages.length > 0) {
+						let lastMsg = buf.messages[buf.messages.length - 1];
+						receipts[ReceiptType.READ] = receiptFromMessage(lastMsg);
+					}
+
 					let client = app.clients.get(buf.server);
 					app.bufferStore.put({
 						name: buf.name,
 						server: client.params,
 						unread: Unread.NONE,
+						receipts,
 					});
 				});
 				return { buffers };

state.js

@@ -85,6 +85,16 @@ export function getServerName(server, bouncerNetwork) {
 	}
 }
 
+export function receiptFromMessage(msg) {
+	// At this point all messages are supposed to have a time tag.
+	// App.addMessage ensures this is the case even if the server doesn't
+	// support server-time.
+	if (!msg.tags.time) {
+		throw new Error("Missing time message tag");
+	}
+	return { time: msg.tags.time };
+}
+
 export function isMessageBeforeReceipt(msg, receipt) {
 	if (!receipt) {
 		return false;