21.5.3: How to corrupt screen and create additional (spurious?) X Window.

(Installation and screen snapshot below.) 1. Start xemacs -q -no-site-file 2. (BTW, the gutter appears as plain grey -- no tabs.) 3. Turn off toolbar: Menu Options -> Display -> Toolbars visible 4. Move gutter to left: Menu Options -> Display -> Default gutter location -> Left. 5. An additional X Window appears at (0,0), with no title or contents (see screen shot). XEmacs prints: Gtk-CRITICAL **: file gtkwidget.c: line 3722 (gtk_widget_get_parent_window): assertion `widget->parent != NULL' failed. Tim timw dot edml dot co dot nz uname -a: Linux chromium.edml 2.4.9-12 #1 Tue Oct 30 18:16:30 EST 2001 i586 unknown ./configure '--prefix=/home/app/xemacs-21.5.3' '--with-gtk' '--with-gnome' '--with-pop' XEmacs 21.5-b3 "asparagus" configured for `i586-pc-linux'. Compilation / Installation: Source code location: /home/app/src/xemacs-21.5.3 Installation prefix: /home/app/xemacs-21.5.3 Operating system description file: `s/linux.h' Machine description file: `m/intel386.h' Compiler: gcc -g -O3 -Wall -Wno-switch -Winline -Wmissing-prototypes -Wshadow -Wsign-compare Relocating allocator for buffers: no GNU version of malloc: yes - Using Doug Lea's new malloc from the GNU C Library. Window System: Using GTK menubars. Using GTK scrollbars. Using GTK dialog boxes. Using GTK native widgets. TTY: Compiling in support for ncurses. Compiling in support for GPM (General Purpose Mouse). Images: Compiling in support for GIF images (builtin). Compiling in support for XPM images. Compiling in support for PNG images. Compiling in support for JPEG images. Compiling in support for TIFF images. Sound: Compiling in support for sound (native). Compiling in support for ESD (Enlightened Sound Daemon). Databases: Compiling in support for Berkeley database. Compiling in support for LDAP. Internationalization: Mail: Compiling in support for POP mail retrieval. Compiling in support for "dot-locking" mail spool file locking method. Other Features: Compiling in support for dynamic shared object modules. Compiling in support for extra debugging code. WARNING: --------------------------------------------------------- WARNING: Compiling in support for runtime error checking. WARNING: XEmacs will run noticeably more slowly as a result. WARNING: Error checking is on by default for XEmacs beta releases. WARNING: ---------------------------------------------------------