[Bug 56011] New: regression: explorer/systray.c crash when WM_USER + 1 signal sent (eg on WM lock/unlock cycle)

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56011

Bug ID: 56011
           Summary: regression: explorer/systray.c crash when WM_USER + 1
                    signal sent (eg on WM lock/unlock cycle)
           Product: Wine
           Version: 9.0-rc1
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: explorerframe
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 75632
  --> https://bugs.winehq.org/attachment.cgi?id=75632
screenshot showing line 574 nb_displayed error

Regression introduced in 48e6bf3cf1aabdd2ac640f572416b9169e324f21, present in
Wine 9.0-rc1

Assert at
https://github.com/wine-mirror/wine/blob/wine-9.0-rc1/programs/explorer/syst...
`assert(nb_displayed)` fails inside of WM_USER + 1 case in which hide_icon() is
called by WM, while nb_displayed is not currently true.

Repro case: trigger systray_atom(), for instance locking screen (causing the
wine systray to hide because wine is sensitive / not allowed to appear in unity
systray while locked), then unlocking screen, causing the systray event to fire
and a second hide attempted while already hidden.