https://bugs.winehq.org/show_bug.cgi?id=38588
--- Comment #6 from Olivier F. R. Dierick o.dierick@piezo-forte.be --- I'm confused.
Tried on a fresh 64-bit wineprefix and got the same result as with a fresh 32-bit wineprefix: Crash when closing Steam the first time, then no more crash on subsequent runs.
When I reported the bug I was using an existing wineprefix with an existing Steam install with a game. Maybe the issue is triggered by a window component installed by the game.
I'll try to install that game into the fresh wineprefix and see if it triggers the issue.