Add "Edit post" procedure to "Moderator Instructions"

content/categories/staff/moderation/_topics/moderator-instructions/1.md

@@ -42,6 +42,7 @@ For an overview of the Discourse moderation system, see the "[**Discourse Modera
   - [Close topic](#close-topic)
   - [Delete post](#delete-post)
   - [Delete topic](#delete-topic)
+  - [Edit post](#edit-post)
   - [Flag post](#flag-post)
   - [Investigate user](#investigate-user)
     - [User Notes](#user-notes)
@@ -705,6 +706,33 @@ Closing a topic will prevent any further replies by non-staff users.
 
 ---
 
+<a name="edit-post"></a>
+
+### [Edit post](#edit-post)
+
+A otherwise valuable post may contain unwanted content. For example:
+
+- incidental profanity
+- content rendered obsolete by moderation
+
+In this case, the unwanted content should be edited out of the post rather than deleting the post.
+
+1. Click the **⬤⬤⬤** icon at the bottom of the post.
+   Additional icons will appear.
+1. Click the pencil icon ("edit this post") at the bottom of the post.
+   The post will open in the post composer panel.
+1. Adjust the post content.
+1. Click the **ⓘ** icon at the top of the post composer panel.
+   A "why are you editing?" text field will appear.
+1. Type an explanation for the edit in the field.
+1. Click the "**Save Edit**" button at the bottom of the post composer panel.
+
+---
+
+❗ _**Do not**_ pollute the post by add meta-content such as a changelog or explanation for the edit to the post content. The changeset and explanation provided by the "why are you editing?" field can be seen via the post edit history dialog.
+
+---
+
 <a name="flag-post"></a>
 
 ### [Flag post](#flag-post)