fix: #8410

public/src/client/topic/diffs.js

@@ -44,7 +44,7 @@ define('forum/topic/diffs', ['forum/topic/images', 'benchpress', 'translator'],
 
 					selectEl.on('change', function () {
 						Diffs.load(pid, this.value, postContainer);
-						revertEl.prop('disabled', data.timestamps.indexOf(this.value) === -1);
+						revertEl.prop('disabled', data.timestamps.indexOf(this.value) === 0);
 					});
 
 					revertEl.on('click', function () {

src/posts/diffs.js

@@ -24,7 +24,7 @@ module.exports = function (Posts) {
 	Diffs.get = async function (pid, since) {
 		const timestamps = await Diffs.list(pid);
 		// Pass those made after `since`, and create keys
-		const keys = timestamps.filter(t => (parseInt(t, 10) || 0) >= since)
+		const keys = timestamps.filter(t => (parseInt(t, 10) || 0) > since)
 			.map(t => 'diff:' + pid + '.' + t);
 		return await db.getObjects(keys);
 	};

src/socket.io/posts/diffs.js

@@ -10,7 +10,8 @@ module.exports = function (SocketPosts) {
 		const timestamps = await posts.diffs.list(data.pid);
 		const cid = await posts.getCidByPid(data.pid);
 		const canEdit = await privileges.categories.can('edit', cid, socket.uid);
-		timestamps.unshift(Date.now());
+		const postTime = await posts.getPostField(data.pid, 'timestamp');
+		timestamps.push(postTime);
 		return {
 			timestamps: timestamps,
 			editable: canEdit,