diff --git a/matrix/config.py b/matrix/config.py
index a073959..2d8c0ac 100644
--- a/matrix/config.py
+++ b/matrix/config.py
@@ -22,9 +22,9 @@ from matrix.plugin_options import (
     ServerBufferType
 )
 
-from matrix.globals import W, OPTIONS, CONFIG
+from matrix.globals import W, OPTIONS, CONFIG, SERVERS
 from matrix.utf import utf8_decode
-from matrix.utils import key_from_value
+from matrix.utils import key_from_value, server_buffer_merge
 from matrix.commands import hook_page_up
 
 
@@ -39,13 +39,19 @@ def matrix_config_change_cb(data, option):
 
     if option_name == "redactions":
         OPTIONS.redaction_type = RedactType(W.config_integer(option))
+
     elif option_name == "server_buffer":
         OPTIONS.look_server_buf = ServerBufferType(
             W.config_integer(option))
+        for server in SERVERS.values():
+            server_buffer_merge(server.server_buffer)
+
     elif option_name == "max_initial_sync_events":
         OPTIONS.sync_limit = W.config_integer(option)
+
     elif option_name == "max_backlog_sync_events":
         OPTIONS.backlog_limit = W.config_integer(option)
+
     elif option_name == "fetch_backlog_on_pgup":
         OPTIONS.enable_backlog = W.config_boolean(option)
 
diff --git a/matrix/utils.py b/matrix/utils.py
index 749600e..f057a5d 100644
--- a/matrix/utils.py
+++ b/matrix/utils.py
@@ -18,13 +18,10 @@ from __future__ import unicode_literals
 
 import time
 
-import matrix.globals
+from matrix.globals import W, SERVERS, OPTIONS
 
 from matrix.plugin_options import ServerBufferType
 
-W = matrix.globals.W
-GLOBAL_OPTIONS = matrix.globals.OPTIONS
-
 
 def key_from_value(dictionary, value):
     # type: (Dict[str, Any], Any) -> str
@@ -32,7 +29,7 @@ def key_from_value(dictionary, value):
 
 
 def prnt_debug(debug_type, server, message):
-    if debug_type in GLOBAL_OPTIONS.debug:
+    if debug_type in OPTIONS.debug:
         W.prnt(server.server_buffer, message)
 
 
@@ -77,13 +74,23 @@ def create_server_buffer(server):
     W.buffer_set(server.server_buffer, "localvar_set_server", server.name)
     W.buffer_set(server.server_buffer, "localvar_set_channel", server.name)
 
-    # TODO merge without core
-    if GLOBAL_OPTIONS.look_server_buf == ServerBufferType.MERGE_CORE:
-        W.buffer_merge(server.server_buffer, W.buffer_search_main())
-    elif GLOBAL_OPTIONS.look_server_buf == ServerBufferType.MERGE:
-        pass
+    server_buffer_merge(server.server_buffer)
+
+
+def server_buffer_merge(buffer):
+    if OPTIONS.look_server_buf == ServerBufferType.MERGE_CORE:
+        num = W.buffer_get_integer(W.buffer_search_main(), "number")
+        W.buffer_unmerge(buffer, num + 1)
+        W.buffer_merge(buffer, W.buffer_search_main())
+    elif OPTIONS.look_server_buf == ServerBufferType.MERGE:
+        if SERVERS:
+            first = list(SERVERS.values())[0].server_buffer
+            num = W.buffer_get_integer(W.buffer_search_main(), "number")
+            W.buffer_unmerge(buffer, num + 1)
+            W.buffer_merge(buffer, first)
     else:
-        pass
+        num = W.buffer_get_integer(W.buffer_search_main(), "number")
+        W.buffer_unmerge(buffer, num + 1)
 
 
 def server_buffer_set_title(server):