diff --git a/public/src/client/topic/replies.js b/public/src/client/topic/replies.js
index a70862c119..20633935ef 100644
--- a/public/src/client/topic/replies.js
+++ b/public/src/client/topic/replies.js
@@ -14,7 +14,7 @@ define('forum/topic/replies', ['forum/topic/posts', 'hooks', 'alerts', 'api'], f
 		if (open.is(':not(.hidden)') && loading.is('.hidden')) {
 			open.addClass('hidden');
 			loading.removeClass('hidden');
-			api.get(`/posts/${pid}/replies`, {}, function (err, { replies }) {
+			api.get(`/posts/${encodeURIComponent(pid)}/replies`, {}, function (err, { replies }) {
 				const postData = replies;
 				loading.addClass('hidden');
 				if (err) {
diff --git a/src/api/posts.js b/src/api/posts.js
index 603e3bf2aa..3a1666b075 100644
--- a/src/api/posts.js
+++ b/src/api/posts.js
@@ -12,6 +12,7 @@ const plugins = require('../plugins');
 const meta = require('../meta');
 const events = require('../events');
 const privileges = require('../privileges');
+const activitypub = require('../activitypub');
 const apiHelpers = require('./helpers');
 const websockets = require('../socket.io');
 const socketHelpers = require('../socket.io/helpers');
@@ -390,7 +391,7 @@ postsAPI.deleteDiff = async (caller, { pid, timestamp }) => {
 };
 
 postsAPI.getReplies = async (caller, { pid }) => {
-	if (!utils.isNumber(pid)) {
+	if (!utils.isNumber(pid) && !activitypub.helpers.isUri(pid)) {
 		throw new Error('[[error:invalid-data]]');
 	}
 	const { uid } = caller;
diff --git a/src/controllers/activitypub/topics.js b/src/controllers/activitypub/topics.js
index fc5cdea85a..bc2152bb2a 100644
--- a/src/controllers/activitypub/topics.js
+++ b/src/controllers/activitypub/topics.js
@@ -5,6 +5,7 @@ const nconf = require('nconf');
 const db = require('../../database');
 const user = require('../../user');
 const topics = require('../../topics');
+const privileges = require('../../privileges');
 
 const { notes } = require('../../activitypub');
 // const helpers = require('../helpers');
@@ -23,11 +24,11 @@ controller.get = async function (req, res, next) {
 
 	let postIndex = await db.sortedSetRank(`tidRemote:${tid}:posts`, req.query.resource);
 	const [
-		// userPrivileges,
+		userPrivileges,
 		settings,
 		// topicData,
 	] = await Promise.all([
-		// privileges.topics.get(tid, req.uid),
+		privileges.topics.get(tid, req.uid),
 		user.getSettings(req.uid),
 		// topics.getTopicData(tid),
 	]);
@@ -40,7 +41,7 @@ controller.get = async function (req, res, next) {
 	const invalidPagination = (settings.usePagination && (currentPage < 1 || currentPage > pageCount));
 	if (
 		!topicData ||
-		// userPrivileges.disabled ||
+		userPrivileges.disabled ||
 		invalidPagination// ||
 		// (topicData.scheduled && !userPrivileges.view_scheduled)
 	) {
@@ -62,6 +63,7 @@ controller.get = async function (req, res, next) {
 	topicData.posts = await notes.getTopicPosts(tid, req.uid, start, stop);
 	await topics.calculatePostIndices(topicData.posts, start - 1);
 	topicData.posts = await topics.addPostData(topicData.posts, req.uid);
+	topicData.privileges = userPrivileges;
 
 	await topics.increaseViewCount(req, tid);
 
diff --git a/src/posts/category.js b/src/posts/category.js
index d5f4874cc1..b87342a89f 100644
--- a/src/posts/category.js
+++ b/src/posts/category.js
@@ -6,10 +6,15 @@ const _ = require('lodash');
 
 const db = require('../database');
 const topics = require('../topics');
+const activitypub = require('../activitypub');
 
 module.exports = function (Posts) {
 	Posts.getCidByPid = async function (pid) {
 		const tid = await Posts.getPostField(pid, 'tid');
+		if (!tid && activitypub.helpers.isUri(pid)) {
+			return -1; // fediverse pseudo-category
+		}
+
 		return await topics.getTopicField(tid, 'cid');
 	};