50 seems like a better default

docs/CHANGES.md

@@ -19,7 +19,7 @@
 - The no-jQuery build has been renamed from `converse.nojquery.js` to
   `converse-no-jquery.js` to fit the convention used for other build names.
   [jcbrand]
-- 100 is the new default [archived_messages_page_size](https://conversejs.org/docs/html/configuration.html#archived-messages-page-size)
+- 50 is the new default [archived_messages_page_size](https://conversejs.org/docs/html/configuration.html#archived-messages-page-size)
   [jcbrand]
 - Better support for delayed delivery of presence stanzas (XEP-0203). [jcbrand]
 - The chat room `description` is now shown in the heading, not the `subject`.

docs/source/configuration.rst

@@ -211,7 +211,7 @@ Show animations, for example when opening and closing chat boxes.
 archived_messages_page_size
 ---------------------------
 
-* Default:  ``100``
+* Default:  ``50``
 
 See also: `message_archiving`_
 

src/converse-mam.js

@@ -181,7 +181,7 @@
             var _converse = this._converse;
 
             this.updateSettings({
-                archived_messages_page_size: '100',
+                archived_messages_page_size: '50',
                 message_archiving: undefined, // Supported values are 'always', 'never', 'roster' (https://xmpp.org/extensions/xep-0313.html#prefs)
                 message_archiving_timeout: 8000, // Time (in milliseconds) to wait before aborting MAM request
             });