User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.4) Gecko/2008102920 Firefox/3.0.4 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.4) Gecko/2008102920 Firefox/3.0.4 With Firefox 3 I am seeing that my Plugin is being instantiated and then shutdown multiple times from the same page. In FF2 the same plugin worked fine - the Plugin was instantiated once until a new page load. Is there a way to control the calls to NS_NewPluginInstance in FF3? I am adding a code snippet here to show how my plugin objects are getting re-initialized. The Plugin, once re-inistantiated, cannot remember its earlier state. Here is a code snippet: nsPluginInstanceBase * NS_NewPluginInstance(nsPluginCreateData* aCreateDataStruct) { if(!aCreateDataStruct) return NULL; // this tells Mozilla that we are windowless // NPN_SetValue(aCreateDataStruct->instance, NPPVpluginWindowBool, NULL); nsPluginInstance * plugin = new nsPluginInstance( aCreateDataStruct->instance, aCreateDataStruct->argc, aCreateDataStruct->argn, aCreateDataStruct->argv ); return plugin; } nsPluginInstance::nsPluginInstance(NPP aInstance, int argc, char** argn, char** argv) { .... // Initialize all the Plugin objects --> !!! I cannot differentiate between a first time initialization and a re-initialization within the same page. ... } Reproducible: Always Steps to Reproduce: 1. 2. 3.