diff --git a/public/language/en-GB/admin/settings/activitypub.json b/public/language/en-GB/admin/settings/activitypub.json
index 1b00672e0f..5ab4fa43e8 100644
--- a/public/language/en-GB/admin/settings/activitypub.json
+++ b/public/language/en-GB/admin/settings/activitypub.json
@@ -22,8 +22,9 @@
 	"rules-intro": "Content discovered via ActivityPub can be automatically categorized based on certain rules (e.g. hashtag)",
 	"rules.modal.title": "How it works",
 	"rules.modal.instructions": "Any incoming content is checked against these categorization rules, and matching content is automatically moved into the category of choice.<br /><br /><strong>N.B.</strong> Content that is already categorized (i.e. in a remote category) will not pass through these rules.",
-	"rules.modal.values-multiple": "To match multiple values, separate entries with a comma (e.g. <code>one,two,three</code>)",
 	"rules.add": "Add New Rule",
+	"rules.help-hashtag": "Topics containing this case-insensitive hashtag will match. Do not enter the <code>#</code> symbol",
+	"rules.help-user": "Topics created by the entered user will match. Enter a handle or full ID (e.g. <code>bob@example.org</code> or <code>https://example.org/users/bob</code>.",
 	"rules.type": "Type",
 	"rules.value": "Value",
 	"rules.cid": "Category",
diff --git a/public/src/admin/settings/activitypub.js b/public/src/admin/settings/activitypub.js
index 8c79d95b4b..0da00293de 100644
--- a/public/src/admin/settings/activitypub.js
+++ b/public/src/admin/settings/activitypub.js
@@ -6,7 +6,8 @@ define('admin/settings/activitypub', [
 	'categorySelector',
 	'api',
 	'alerts',
-], function (Benchpress, bootbox, categorySelector, api, alerts) {
+	'translator',
+], function (Benchpress, bootbox, categorySelector, api, alerts, translator) {
 	const Module = {};
 
 	Module.init = function () {
@@ -95,6 +96,21 @@ define('admin/settings/activitypub', [
 				modal.find('input').focus();
 			});
 
+
+			// help text
+			const updateHelp = async (key, el) => {
+				const text = await translator.translate(`[[admin/settings/activitypub:rules.help-${key}]]`);
+				el.innerHTML = text;
+			};
+			const helpTextEl = modal.get(0).querySelector('#help-text');
+			const typeEl = modal.get(0).querySelector('#type');
+			updateHelp(modal.get(0).querySelector('#type option').value, helpTextEl);
+			if (typeEl && helpTextEl) {
+				typeEl.addEventListener('change', function () {
+					updateHelp(this.value, helpTextEl);
+				});
+			}
+
 			// category switcher
 			categorySelector.init(modal.find('[component="category-selector"]'), {
 				onSelect: function (selectedCategory) {
diff --git a/src/activitypub/notes.js b/src/activitypub/notes.js
index 3a00323859..cc5e7fe393 100644
--- a/src/activitypub/notes.js
+++ b/src/activitypub/notes.js
@@ -417,6 +417,13 @@ async function assignCategory(post) {
 					}
 					break;
 				}
+
+				case 'user': {
+					if (post.uid === value) {
+						activitypub.helpers.log(`[activitypub]   - Rule match: user ${value}; cid: ${target}`);
+						return target;
+					}
+				}
 			}
 		}
 
diff --git a/src/activitypub/rules.js b/src/activitypub/rules.js
index 3a9a560552..9b3a002aab 100644
--- a/src/activitypub/rules.js
+++ b/src/activitypub/rules.js
@@ -3,6 +3,8 @@
 const db = require('../database');
 const utils = require('../utils');
 
+const activitypub = require('.');
+
 const Rules = module.exports;
 
 Rules.list = async () => {
@@ -19,6 +21,15 @@ Rules.list = async () => {
 Rules.add = async (type, value, cid) => {
 	const uuid = utils.generateUUID();
 
+	// normalize user rule values into a uid
+	if (type === 'user' && value.indexOf('@') !== -1) {
+		const response = await activitypub.actors.assert(value);
+		if (!response) {
+			throw new Error('[[error:no-user]]');
+		}
+		value = await db.getObjectField('handle:uid', String(value).toLowerCase());
+	}
+
 	await Promise.all([
 		db.setObject(`rid:${uuid}`, { type, value, cid }),
 		db.sortedSetAdd('categorization:rid', Date.now(), uuid),
diff --git a/src/views/admin/partials/activitypub/rules.tpl b/src/views/admin/partials/activitypub/rules.tpl
index e321a86744..33273942b5 100644
--- a/src/views/admin/partials/activitypub/rules.tpl
+++ b/src/views/admin/partials/activitypub/rules.tpl
@@ -8,13 +8,14 @@
 		<label class="form-label" for="type">Type</label>
 		<select class="form-control" name="type" id="type">
 			<option value="hashtag">Hashtag</option>
+			<option value="user">User</option>
 			<!--<option value="content">Content contains...</option>-->
 		</select>
 	</div>
 	<div class="mb-3">
 		<label class="form-label" for="value">Value</label>
 		<input type="text" id="value" name="value" title="Value" class="form-control" placeholder="forum">
-		<p class="form-text">[[admin/settings/activitypub:rules.modal.values-multiple]]</p>
+		<p class="form-text" id="help-text"></p>
 	</div>
 	<div class="mb-3">
 		<label class="form-label">Category</label>