diff --git a/src/map.c b/src/map.c
index 526ed50..e99da37 100644
--- a/src/map.c
+++ b/src/map.c
@@ -1753,7 +1753,11 @@
 	d = res;
 	for (s = p; *s != NUL; )
 	{
-	    if (s[0] == K_SPECIAL && s[1] != NUL && s[2] != NUL)
+	    if ((s[0] == K_SPECIAL
+#ifdef FEAT_GUI
+		    || (gui.in_use && s[0] == CSI)
+#endif
+		) && s[1] != NUL && s[2] != NUL)
 	    {
 		// Copy special key unmodified.
 		*d++ = *s++;
diff --git a/src/testdir/test_gui.vim b/src/testdir/test_gui.vim
index 447eee8..8ac0985 100644
--- a/src/testdir/test_gui.vim
+++ b/src/testdir/test_gui.vim
@@ -1732,4 +1732,23 @@
   bw!
 endfunc
 
+func Test_gui_macro_csi()
+  " Test for issue #11270
+  nnoremap <C-L> <Cmd>let g:triggered = 1<CR>
+  let @q = "\x9b\xfc\x04L"
+  norm @q
+  call assert_equal(1, g:triggered)
+  unlet g:triggered
+  nunmap <C-L>
+
+  " Test for issue #11057
+  inoremap <C-D>t bbb
+  call setline(1, "\t")
+  let @q = "i\x9b\xfc\x04D"
+  " The end of :normal is like a mapping timing out
+  norm @q
+  call assert_equal('', getline(1))
+  iunmap <C-D>t
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index ce0dce0..3adb513 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    660,
+/**/
     659,
 /**/
     658,