New version of Steam causing FVWM to crash when setting background with 'fvwm-root -r'

[sebaro]

Thanks for reporting your bug here! The following template will help with
giving as much information as possible so that it's easier to diagnose and
fix.

Upfront Information

Please provide the following information by running the command and providing
the output.

• Fvwm3 version (run: fvwm3 --version)
  fvwm3 1.0.7 (1.0.6a-17-g01908e29)
  with support for: XPM, PNG, SVG, Shape, XShm, SM, XRandR, XRender, XCursor, XFT, NLS

• Linux distribution or BSD name/version
  Gentoo

• Platform (run: uname -sp)
  Linux AMD Athlon(tm) 5350 APU with Radeon(tm) R3

Expected Behaviour

FVWM doesn't crash

Actual Behaviour

Setting background with 'fvwm-root -r' makes FVWM crash when starting Steam, it doesn't crash without the -r/--retain-pixmap.

Steam log:

(steam:15448): GLib-GObject-CRITICAL **: 12:16:45.201: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(steam:15448): GLib-GObject-CRITICAL **: 12:16:45.201: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
X Error of failed request: BadDrawable (invalid Pixmap or Window parameter)
Major opcode of failed request: 70 (X_PolyFillRectangle)
Resource id in failed request: 0x4009fc
Serial number of failed request: 13774
Current serial number in output stream: 13784
xinit: connection to X server lost

[ThomasAdam]

Hey @sebaro

Can you capture the output from xprop -spy -root prior to FVWM crashing, please?

[sebaro]

xprop.log

[sebaro]

Doesn't crash with the newest Steam version:

Steam Version:  1690583737
Steam Client Build Date:  Fri, Jul 28 9:44 PM UTC +02:00
Steam Web Build Date:  Sat, Jul 29 1:21 AM UTC +02:00
Steam API Version:  SteamClient020