diff --git a/src/testdir/test_popupwin.vim b/src/testdir/test_popupwin.vim
index 333e9a2..6607ea2 100644
--- a/src/testdir/test_popupwin.vim
+++ b/src/testdir/test_popupwin.vim
@@ -1539,6 +1539,23 @@
   call popup_clear()
 endfunc
 
+" this tests that the "ex_normal_busy_done" flag works
+func Test_popup_filter_normal_cmd()
+  CheckScreendump
+
+  let lines =<< trim END
+      let g:winid = popup_create('some text', {'filter': 'invalidfilter'})
+      call timer_start(0, {-> win_execute(g:winid, 'norm! zz')})
+  END
+  call writefile(lines, 'XtestPopupNormal')
+  let buf = RunVimInTerminal('-S XtestPopupNormal', #{rows: 10})
+  call TermWait(buf, 100)
+  call VerifyScreenDump(buf, 'Test_popupwin_normal_cmd', {})
+
+  call StopVimInTerminal(buf)
+  call delete('XtestPopupNormal')
+endfunc
+
 func ShowDialog(key, result)
   let s:cb_res = 999
   let winid = popup_dialog('do you want to quit (Yes/no)?', #{