add documentation and fix timestamp related bugs

Author: fourjr

CHANGELOG.md

@@ -21,6 +21,7 @@ v3.10 adds group conversations while resolving other bugs and QOL changes. It is
 - Snippets are invoked case insensitively. ([GH #3077](https://github.com/kyb3r/modmail/issues/3077), [PR #3080](https://github.com/kyb3r/modmail/pull/3080))
 - Default tags now use top hoisted role. ([GH #3014](https://github.com/kyb3r/modmail/issues/3014))
 - New thread-related config - `thread_show_roles`, `thread_show_account_age`, `thread_show_join_age`, `thread_cancelled`, `thread_creation_contact_title`, `thread_creation_self_contact_response`, `thread_creation_contact_response`. ([GH #3072](https://github.com/kyb3r/modmail/issues/3072))
+- `use_timestamp_channel_name` config to create thread channels by timestamp.
 
 ### Fixed
 

core/config_help.json

@@ -105,7 +105,22 @@
       "`{prefix}config set use_user_id_channel_name no`"
     ],
     "notes": [
-      "This config is suitable for servers in Server Discovery to comply with channel name restrictions."
+      "This config is suitable for servers in Server Discovery to comply with channel name restrictions.",
+      "This cannot be applied with `use_timestamp_channel_name`.",
+      "See also: `use_timestamp_channel_name`."
+    ]
+  },
+  "use_timestamp_channel_name": {
+    "default": "No",
+    "description": "When this is set to `yes`, new thread channels will be named with the recipient's account creation date instead of the recipient's name.",
+    "examples": [
+      "`{prefix}config set use_timestamp_channel_name yes`",
+      "`{prefix}config set use_timestamp_channel_name no`"
+    ],
+    "notes": [
+      "This config is suitable for servers in Server Discovery to comply with channel name restrictions.",
+      "This cannot be applied with `use_user_id_channel_name`.",
+      "See also: `use_user_id_channel_name`."
     ]
   },
   "mod_typing": {

core/utils.py

@@ -1,5 +1,4 @@
 import base64
-from datetime import datetime
 import functools
 import re
 import string
@@ -375,7 +374,7 @@ def format_channel_name(bot, author, exclude_channel=None, force_null=False):
         if bot.config["use_user_id_channel_name"]:
             name = new_name = str(author.id)
         elif bot.config["use_timestamp_channel_name"]:
-            name = new_name = datetime.utcnow().isoformat(sep="-", timesep="minutes")
+            name = new_name = author.created_at.isoformat(sep="-", timespec="minutes")
         else:
             name = author.name.lower()
             if force_null: