https://git.reactos.org/?p=reactos.git;a=commitdiff;h=59d4c1120310b7c08641c…
commit 59d4c1120310b7c08641cc3aab82072251900d98
Author:     Katayama Hirofumi MZ <katayama.hirofumi.mz(a)gmail.com>
AuthorDate: Tue Jun 1 11:11:23 2021 +0900
Commit:     GitHub <noreply(a)github.com>
CommitDate: Tue Jun 1 11:11:23 2021 +0900
    [WIN32SS][NTUSER] ShowWindow.SW_MINIMIZE should show window (#3700)
    - user32!ShowWindow.SW_MINIMIZE should show the window.
    - Fix the return value of ShowWindow function on invalid parameter.
    CORE-15669
---
 win32ss/user/ntuser/winpos.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/win32ss/user/ntuser/winpos.c b/win32ss/user/ntuser/winpos.c
index 71cf8a1cf8d..550a074c6c1 100644
--- a/win32ss/user/ntuser/winpos.c
+++ b/win32ss/user/ntuser/winpos.c
@@ -2560,9 +2560,8 @@ co_WinPosShowWindow(PWND Wnd, INT Cmd)
          Swp |= SWP_NOACTIVATE | SWP_NOZORDER;
          /* Fall through. */
       case SW_SHOWMINIMIZED:
+      case SW_MINIMIZE: /* CORE-15669: SW_MINIMIZE also shows */
          Swp |= SWP_SHOWWINDOW;
-         /* Fall through. */
-      case SW_MINIMIZE:
          {
             Swp |= SWP_NOACTIVATE;
             if (!(style & WS_MINIMIZE))
@@ -2657,7 +2656,7 @@ co_WinPosShowWindow(PWND Wnd, INT Cmd)
       default:
          //ERR("co_WinPosShowWindow Exit Good 4\n");
-         return WasVisible;
+         return FALSE;
    }
    ShowFlag = (Cmd != SW_HIDE);