Plug-in not displaying

With the most recent update to Gutenberg (both 8.9.0. and the recent patch 8.9.1), my Display Post Types plug-in has stopped displaying on the page and in the visual block editor.

When the page first loads in the editor, the outlines of the plugin can be seen (without any content) and if selected, the block settings panel can be accessed. After a few seconds the plug-in shrinks down to a line (the line can be selected and the block settings panel can still be accessed). In neither event, does tweaking the block settings affect what can be seen in the editor or what can be seen on the page itself.

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