Here is a relatively minimal fvwm configuration file that shows the problem for me (inside an Xephyr server):
# Relatively minimal FVWM configuration for reproducing FvwmIconMan # button rendering/colour issues. # # USAGE: use the right button on the root window to call up the main menu # and run some xterms so that FvwmIconMan has something in it. # # Use Close / Start IconMan to close the running FvwmIconMan and restart # it, for example if you have a new version to test. # # (Probably not all of this is absolutely necessary, but there you go.) ExecUseSHELL /bin/sh DestroyMenu Blit AddToMenu Blit "XTerm" Exec xterm -ut -n local & + "Maximize" Maximize + "Reshape" Resize + "Move" Move + "Top" Raise + "Bottom" Lower + "Close" Delete + "Delete" Destroy + "Start IconMan" Module FvwmIconMan # done Blit. # Force all mouse buttons to be allowed for placement. Sigh. Mouse 0 P N PlaceWindow Mouse 3 R N PopUp Blit Mouse 3 RWT M PopUp Blit Style * EdgeMoveResistance 16 250 Style "*" IconTitleFormat %i Style "*" SloppyFocus Style "*" DecorateTransient Style "*" MWMDecor Style "*" MWMFunctions Style "*" HintOverride Style "*" ManualPlacement Style "*" IconBox none Style "*" !UsePPosition Style "*" IconBackgroundRelief 0 OpaqueMoveSize 100 ColormapFocus FollowsFocus BugOpts TransliterateUtf8 TitleStyle MinHeight 20 MenuStyle * FVWM MenuStyle * Foreground black, Background RosyBrown, Greyed SlateGrey MenuStyle * DoubleClickTime 0 Style "*" HilightFore black, HilightBack #60c0a0 Style "*" Color black/PeachPuff3 Style "*" Icon xlogo32 TitleStyle ActiveUp (HGradient 128 #60c0a0 #C0E0D5) ActiveDown (HGradient 128 #60c0a0 #C0E0D5) Inactive (HGradient 128 PeachPuff3 #EFE8E3) MenuStyle * MenuFace VGradient 128 RosyBrown #C69999 MenuStyle * Font "xft:Sans:Condensed Bold:pixelsize=17:encoding=iso10646-1" DefaultFont xft:Sans:pixelsize=16:encoding=iso10646-1 Style * Font "xft:Sans:Bold:pixelsize=12:encoding=iso10646-1" Style * IconFont "xft:Sans:Regular:pixelsize=12:encoding=iso10646-1" TitleStyle LeftJustified Mouse 1 1 N Iconify Mouse 1 3 N Stick Mouse 1 4 N Delete Mouse 1 2 N Maximize ButtonStyle 1 - !MWMDecorMin !MWMDecorMax !MWMDecorMenu ButtonStyle 2 - !MWMDecorMin !MWMDecorMax !MWMDecorMenu ButtonStyle 3 - !MWMDecorMin !MWMDecorMax !MWMDecorMenu ButtonStyle 4 - !MWMDecorMin !MWMDecorMax !MWMDecorMenu Style "plan9" !Title, HandleWidth 5, BorderWidth 5 Style "terminal" UseStyle plan9, !Icon, StickyIcon, State 2 Style "XTerm" UseStyle terminal DestroyModuleConfig FvwmIconMan Style "FvwmIconMan" !Title, HandleWidth 0, BorderWidth 0, Sticky *FvwmIconMan: Font 8x13 *FvwmIconMan: ManagerGeometry 10x0+0+0@1 *FvwmIconMan: ButtonGeometry 100x0 *FvwmIconMan: FollowFocus true *FvwmIconMan: Show class=XTerm class=9term class=Gnome-terminal *FvwmIconMan: Format %i *FvwmIconMan: Sort namewithcase *FvwmIconMan: FocusAndSelectButton flat goldenrod maroon *FvwmIconMan: FocusButton flat goldenrod maroon *FvwmIconMan: SelectButton flat goldenrod maroon *FvwmIconMan: PlainButton up goldenrod maroon *FvwmIconMan: IconButton up goldenrod maroon *FvwmIconMan: Resolution desk *FvwmIconMan: Action Mouse 1 N sendcommand Iconify *FvwmIconMan: Action Mouse 2 N sendcommand Focus *FvwmIconMan: Action Mouse 3 N sendcommand Raise *FvwmIconMan: Shape true *FvwmIconMan: Tips needed *FvwmIconMan: TipsFont "xft:Sans:Regular:pixelsize=12:encoding=iso10646-1" DestroyFunc StartFunction AddToFunc StartFunction + I Test (Start) Module FvwmIconMan ####