diff --git a/src/nvim/ex_getln.c b/src/nvim/ex_getln.c
index 97336a5fd5..4a5f3ad9f6 100644
--- a/src/nvim/ex_getln.c
+++ b/src/nvim/ex_getln.c
@@ -2328,6 +2328,8 @@ static void cmdpreview_restore_undo(const CpUndoInfo *cp_undoinfo, buf_T *buf)
 static void cmdpreview_prepare(CpInfo *cpinfo)
   FUNC_ATTR_NONNULL_ALL
 {
+  PMap(ptr_t) saved_bufs = MAP_INIT;
+
   kv_init(cpinfo->buf_info);
   kv_init(cpinfo->win_info);
 
@@ -2339,19 +2341,19 @@ static void cmdpreview_prepare(CpInfo *cpinfo)
       continue;
     }
 
-    CpBufInfo cp_bufinfo;
-    cp_bufinfo.buf = buf;
+    if (!pmap_has(ptr_t)(&saved_bufs, buf)) {
+      CpBufInfo cp_bufinfo;
+      cp_bufinfo.buf = buf;
+      cp_bufinfo.save_b_p_ul = buf->b_p_ul;
+      cp_bufinfo.save_b_changed = buf->b_changed;
+      cp_bufinfo.save_changedtick = buf_get_changedtick(buf);
+      cmdpreview_save_undo(&cp_bufinfo.undo_info, buf);
+      kv_push(cpinfo->buf_info, cp_bufinfo);
+      pmap_put(ptr_t)(&saved_bufs, buf, NULL);
 
-    cp_bufinfo.save_b_p_ul = buf->b_p_ul;
-    cp_bufinfo.save_b_changed = buf->b_changed;
-    cp_bufinfo.save_changedtick = buf_get_changedtick(buf);
-
-    cmdpreview_save_undo(&cp_bufinfo.undo_info, buf);
-    u_clearall(buf);
-
-    kv_push(cpinfo->buf_info, cp_bufinfo);
-
-    buf->b_p_ul = LONG_MAX;     // Make sure we can undo all changes
+      u_clearall(buf);
+      buf->b_p_ul = LONG_MAX;  // Make sure we can undo all changes
+    }
 
     CpWinInfo cp_wininfo;
     cp_wininfo.win = win;
@@ -2370,6 +2372,8 @@ static void cmdpreview_prepare(CpInfo *cpinfo)
     win->w_p_cuc = false;       // Disable 'cursorcolumn' so it doesn't mess up the highlights
   }
 
+  pmap_destroy(ptr_t)(&saved_bufs);
+
   cpinfo->save_hls = p_hls;
   cpinfo->save_cmdmod = cmdmod;
   win_size_save(&cpinfo->save_view);
@@ -2426,6 +2430,7 @@ static void cmdpreview_restore_state(CpInfo *cpinfo)
     // Clear preview highlights.
     extmark_clear(buf, (uint32_t)cmdpreview_ns, 0, 0, MAXLNUM, MAXCOL);
   }
+
   for (size_t i = 0; i < cpinfo->win_info.size; i++) {
     CpWinInfo cp_wininfo = cpinfo->win_info.items[i];
     win_T *win = cp_wininfo.win;
diff --git a/test/functional/ui/inccommand_spec.lua b/test/functional/ui/inccommand_spec.lua
index 96634be327..7f05f0f901 100644
--- a/test/functional/ui/inccommand_spec.lua
+++ b/test/functional/ui/inccommand_spec.lua
@@ -2,7 +2,6 @@ local helpers = require('test.functional.helpers')(after_each)
 local Screen = require('test.functional.ui.screen')
 local clear = helpers.clear
 local command = helpers.command
-local curbufmeths = helpers.curbufmeths
 local eq = helpers.eq
 local eval = helpers.eval
 local feed_command = helpers.feed_command
@@ -175,11 +174,14 @@ describe(":substitute, 'inccommand' preserves", function()
     it("'undolevels' (inccommand="..case..")", function()
       feed_command("set undolevels=139")
       feed_command("setlocal undolevels=34")
+      feed_command("split")  -- Show the buffer in multiple windows
       feed_command("set inccommand=" .. case)
       insert("as")
-      feed(":%s/as/glork/<enter>")
-      eq(meths.get_option('undolevels'), 139)
-      eq(curbufmeths.get_option('undolevels'), 34)
+      feed(":%s/as/glork/")
+      poke_eventloop()
+      feed("<enter>")
+      eq(meths.get_option_value('undolevels', {scope='global'}), 139)
+      eq(meths.get_option_value('undolevels', {buf=0}), 34)
     end)
   end