Added locale (english only at the moment) and modifed the EJS so I think

every string is customisable (via the /locales/selected locale)

views/forms/edit_post.ejs

@@ -7,13 +7,21 @@
         <form action="/submit_edit_post" method="POST" onsubmit="sha512password()">
             <input name="userID" type="hidden" value="<%= post['userID'] %>">
             <input name="postID" type="hidden" value="<%= post_id %>">
-            <input placeholder="<%= user['prettyname'] %>'s password" type="password" required id="password" name="password"><br/>
-            <input placeholder="title" value=" <%=post['title'] %>" required name="title"><br/>
-            <textarea placeholder="content" required name="content"><%= post['content'] %></textarea><br/>
-            <input placeholder="tags (comma seperated)" value="<%= post['tags'] %>" name="tags"><br/>
+
+            <label><%= locale.password %>:</label><br/>
+            <input type="password" required id="password" name="password"><br/><br/>
+
+            <label><%= locale.title %>:</label><br/>
+            <input value="<%=post['title'] %>" required name="title"><br/><br/>
+
+            <label><%= locale.post_content %>:</label><br/>
+            <textarea required name="content"><%= post['content'] %></textarea><br/><br/>
+
+            <label><%= locale.tags %>:</label><br/>
+            <input value="<%= post['tags'] %>" name="tags"><br/><br/>
+
             <label>Delete forever (no undo): </label><input name="delete" type="checkbox"><br/>
             <input type="submit" value="Submit"><br/>
-            <small>* Markdown supported</small>
         </form>
     </body>
 </html>