Segfault in xfce_arrow_button_get_blinking via libtasklist.so causing panel crash loop

The Component: The Window Buttons plugin (libtasklist.so).

The Trigger Function: xfce_arrow_button_get_blinking in libxfce4panel-2.0.so.4.

The Environment:

• xfce4-panel version 4.20.4
• GTK version 3.24.49
• GLib version 2.84.4

The Stack Trace
Stack trace of thread 599727:
#0  0x00007f01593b7d6d xfce_arrow_button_get_blinking (libxfce4panel-2.0.so.4 + 0x8d6d)
#1  0x00007f015429d269 n/a (libtasklist.so + 0x11269)
#2  0x00007f01583fd950 g_closure_invoke (libgobject-2.0.so.0 + 0x17950)

(Not sure how to attach the dump file here...)