Indesign crash when duplicating or copying the frame after remove the plugin

From HidTxt.fr:

// Custom story thread (ITextStoryThread) and owned item (IOwnedItem) implementations are 
// not supported by missing plug-in workflows. If a document with hidden text is passed to a 
// user that does not have the HiddenText plug-in the application may become unstable and 
// document corruption may happen. Therefore we mark this plug-in's data as critical so the
// user will receive a string warning not to open documents with hidden text data when the
// plug-in is missing.

When you remove your critical plug-in required by a document, that should cause the "missing plug-in" dialogs rather than crash the application. Have you eventually modified the example project by removing these other objects, or the CriticalTags resources ?

Export the documents that used the plugin to .idml to strip ouot the plugin information.

What plugin in are you talking about?

What happens if you export the file as IDML and use that now? 

Maybe you should export to IDML before removing the plugin.

Does this happen with every document or some document that you created with the plugin? Trash InDesign preferences, it might help

-Manan