diff --git a/src/activitypub/notes.js b/src/activitypub/notes.js
index f49cb5113a..2bc4f4f871 100644
--- a/src/activitypub/notes.js
+++ b/src/activitypub/notes.js
@@ -7,6 +7,7 @@ const topics = require('../topics');
 const posts = require('../posts');
 const utils = require('../utils');
 const pubsub = require('../pubsub');
+const slugify = require('../slugify');
 
 const activitypub = module.parent.exports;
 const Notes = module.exports;
@@ -98,7 +99,7 @@ Notes.assertTopic = async (uid, id) => {
 
 	const chain = Array.from(await Notes.getParentChain(uid, id));
 	let { pid: mainPid, tid, uid: authorId, timestamp, name, content } = chain[chain.length - 1];
-	const members = await db.isSortedSetMembers(`tidRemote:${tid}:posts`, chain.map(p => p.pid));
+	const members = await db.isSortedSetMembers(`tid:${tid}:posts`, chain.map(p => p.pid));
 	if (tid && members.every(Boolean)) {
 		// All cached, return early.
 		winston.info('[notes/assertTopic] No new notes to process.');
@@ -121,17 +122,21 @@ Notes.assertTopic = async (uid, id) => {
 		unprocessed.map(n => n.timestamp),
 	];
 
+	// mainPid doesn't belong in posts zset
+	ids.pop();
+	timestamps.pop();
+
 	await Promise.all([
-		db.setObject(`topicRemote:${tid}`, {
+		db.setObject(`topic:${tid}`, {
 			tid,
 			uid: authorId,
 			cid: cid || -1,
 			mainPid,
 			title,
-			slug: `../world/${tid}`,
+			slug: `${tid}/${slugify(title)}`,
 			timestamp,
 		}),
-		db.sortedSetAdd(`tidRemote:${tid}:posts`, timestamps, ids),
+		db.sortedSetAdd(`tid:${tid}:posts`, timestamps, ids),
 		Notes.assert(uid, unprocessed),
 	]);
 	await Promise.all([ // must be done after .assert()
@@ -145,20 +150,20 @@ Notes.assertTopic = async (uid, id) => {
 };
 
 Notes.updateTopicCounts = async function (tid) {
-	const pids = await db.getSortedSetMembers(`tidRemote:${tid}:posts`);
+	const pids = await db.getSortedSetMembers(`tid:${tid}:posts`);
 	let uids = await db.getObjectsFields(pids.map(p => `post:${p}`), ['uid']);
 	uids = uids.reduce((set, { uid }) => {
 		set.add(uid);
 		return set;
 	}, new Set());
 
-	db.setObject(`topicRemote:${tid}`, {
+	db.setObject(`topic:${tid}`, {
 		postercount: uids.size,
 		postcount: pids.length,
 	});
 };
 
 Notes.getTopicPosts = async (tid, uid, start, stop) => {
-	const pids = await db.getSortedSetRange(`tidRemote:${tid}:posts`, start, stop);
+	const pids = await db.getSortedSetRange(`tid:${tid}:posts`, start, stop);
 	return await posts.getPostsByPids(pids, uid);
 };
diff --git a/src/categories/data.js b/src/categories/data.js
index 4568d4850d..49de0a4f4e 100644
--- a/src/categories/data.js
+++ b/src/categories/data.js
@@ -13,6 +13,19 @@ const intFields = [
 	'minTags', 'maxTags', 'postQueue', 'subCategoriesPerPage',
 ];
 
+const worldCategory = {
+	cid: -1,
+	name: 'World',
+	description: '[[error:invalid-data]]',
+	descriptionParsed: 'what',
+	icon: 'fa-globe',
+	bgColor: '#0000ff',
+	color: '#ffffff',
+	slug: '../world',
+	parentCid: 0,
+	disabled: 0, // todo
+};
+
 module.exports = function (Categories) {
 	Categories.getCategoriesFields = async function (cids, fields) {
 		if (!Array.isArray(cids) || !cids.length) {
@@ -21,6 +34,12 @@ module.exports = function (Categories) {
 
 		const keys = cids.map(cid => `category:${cid}`);
 		const categories = await db.getObjects(keys, fields);
+
+		// Handle cid -1
+		if (cids.includes(-1)) {
+			categories.splice(cids.indexOf(-1), 1, worldCategory);
+		}
+
 		const result = await plugins.hooks.fire('filter:category.getFields', {
 			cids: cids,
 			categories: categories,
diff --git a/src/controllers/topics.js b/src/controllers/topics.js
index 7eeb463d89..5324bb9ca6 100644
--- a/src/controllers/topics.js
+++ b/src/controllers/topics.js
@@ -2,6 +2,7 @@
 
 const nconf = require('nconf');
 const qs = require('querystring');
+const validator = require('validator');
 
 const user = require('../user');
 const meta = require('../meta');
@@ -9,14 +10,11 @@ const topics = require('../topics');
 const categories = require('../categories');
 const posts = require('../posts');
 const privileges = require('../privileges');
-const activitypub = require('../activitypub');
 const helpers = require('./helpers');
 const pagination = require('../pagination');
 const utils = require('../utils');
 const analytics = require('../analytics');
 
-const activitypubController = require('./activitypub');
-
 const topicsController = module.exports;
 
 const url = nconf.get('url');
@@ -24,14 +22,10 @@ const relative_path = nconf.get('relative_path');
 const upload_url = nconf.get('upload_url');
 
 topicsController.get = async function getTopic(req, res, next) {
-	if (req.params.topic_id === 'remote' && activitypub.helpers.isUri(req.query.resource)) {
-		return activitypubController.topics.get(req, res, next);
-	}
-
 	const tid = req.params.topic_id;
 	if (
 		(req.params.post_index && !utils.isNumber(req.params.post_index) && req.params.post_index !== 'unread') ||
-		!utils.isNumber(tid)
+		(!utils.isNumber(tid) && !validator.isUUID(tid))
 	) {
 		return next();
 	}
diff --git a/src/socket.io/topics/infinitescroll.js b/src/socket.io/topics/infinitescroll.js
index 3b478154ee..40ccbb4b0c 100644
--- a/src/socket.io/topics/infinitescroll.js
+++ b/src/socket.io/topics/infinitescroll.js
@@ -23,8 +23,7 @@ module.exports = function (SocketTopics) {
 			throw new Error('[[error:no-privileges]]');
 		}
 
-		const setPrefix = validator.isUUID(String(data.tid)) ? 'tidRemote' : 'tid';
-		const set = data.topicPostSort === 'most_votes' ? `${setPrefix}:${data.tid}:posts:votes` : `${setPrefix}:${data.tid}:posts`;
+		const set = data.topicPostSort === 'most_votes' ? `tid:${data.tid}:posts:votes` : `tid:${data.tid}:posts`;
 		const reverse = data.topicPostSort === 'newest_to_oldest' || data.topicPostSort === 'most_votes';
 		let start = Math.max(0, parseInt(data.after, 10));
 
diff --git a/src/topics/data.js b/src/topics/data.js
index 572a86f2be..968c346cbc 100644
--- a/src/topics/data.js
+++ b/src/topics/data.js
@@ -26,7 +26,7 @@ module.exports = function (Topics) {
 			fields.push('timestamp');
 		}
 
-		const keys = tids.map(tid => `${validator.isUUID(String(tid)) ? 'topicRemote' : 'topic'}:${tid}`);
+		const keys = tids.map(tid => `topic:${tid}`);
 		const topics = await db.getObjects(keys, fields);
 		const result = await plugins.hooks.fire('filter:topic.getFields', {
 			tids: tids,
@@ -63,13 +63,11 @@ module.exports = function (Topics) {
 	};
 
 	Topics.setTopicField = async function (tid, field, value) {
-		const setPrefix = validator.isUUID(String(tid)) ? 'topicRemote' : 'topic';
-		await db.setObjectField(`${setPrefix}:${tid}`, field, value);
+		await db.setObjectField(`topic:${tid}`, field, value);
 	};
 
 	Topics.setTopicFields = async function (tid, data) {
-		const setPrefix = validator.isUUID(String(tid)) ? 'topicRemote' : 'topic';
-		await db.setObject(`${setPrefix}:${tid}`, data);
+		await db.setObject(`topic:${tid}`, data);
 	};
 
 	Topics.deleteTopicField = async function (tid, field) {
diff --git a/src/topics/posts.js b/src/topics/posts.js
index d55982f4f3..2605edce31 100644
--- a/src/topics/posts.js
+++ b/src/topics/posts.js
@@ -231,10 +231,9 @@ module.exports = function (Topics) {
 	Topics.getLatestUndeletedReply = async function (tid) {
 		let isDeleted = false;
 		let index = 0;
-		const setPrefix = validator.isUUID(String(tid)) ? 'tidRemote' : 'tid';
 		do {
 			/* eslint-disable no-await-in-loop */
-			const pids = await db.getSortedSetRevRange(`${setPrefix}:${tid}:posts`, index, index);
+			const pids = await db.getSortedSetRevRange(`tid:${tid}:posts`, index, index);
 			if (!pids.length) {
 				return null;
 			}
@@ -312,7 +311,7 @@ module.exports = function (Topics) {
 	};
 
 	async function incrementFieldAndUpdateSortedSet(tid, field, by, set) {
-		const value = await db.incrObjectFieldBy(`${validator.isUUID(String(tid)) ? 'topicRemote' : 'topic'}:${tid}`, field, by);
+		const value = await db.incrObjectFieldBy(`topic:${tid}`, field, by);
 		await db[Array.isArray(set) ? 'sortedSetsAdd' : 'sortedSetAdd'](set, value, tid);
 	}
 
diff --git a/src/topics/recent.js b/src/topics/recent.js
index d360a44f10..bd2236a457 100644
--- a/src/topics/recent.js
+++ b/src/topics/recent.js
@@ -70,13 +70,19 @@ module.exports = function (Topics) {
 	};
 
 	Topics.updateRecent = async function (tid, timestamp) {
-		let data = { tid: tid, timestamp: timestamp };
+		let data = { tid, timestamp };
+
+		// Topics in /world are excluded from /recent
+		const cid = await Topics.getTopicField(tid, 'cid');
+		if (cid === -1) {
+			return;
+		}
+
 		if (plugins.hooks.hasListeners('filter:topics.updateRecent')) {
-			data = await plugins.hooks.fire('filter:topics.updateRecent', { tid: tid, timestamp: timestamp });
+			data = await plugins.hooks.fire('filter:topics.updateRecent', data);
 		}
 		if (data && data.tid && data.timestamp) {
-			const setPrefix = validator.isUUID(String(data.tid)) ? 'topicsRemote' : 'topics';
-			await db.sortedSetAdd(`${setPrefix}:recent`, data.timestamp, data.tid);
+			await db.sortedSetAdd(`topics:recent`, data.timestamp, data.tid);
 		}
 	};
 };