I have been working on an NPAPI plugin. Now it works nicely on Windows and Mac OS X but on Linux/Firefox I get a deadlock. The deadlock occurs because the main thread tries to write to the wakeup_pipe in the MessagePumpForUI class and the wakeup_pipe eventually runs full. Other threads such the the worker threads in my plugin are also writing to this pipe via the NPN_PluginThreadAsync browser interface. It seems like a bad idea that the NPN_PluginThreadAsync can block at all, but it does happen since the main thread is both a reader and writer on the wakeup_pipe. Ideally the writes on the wakeup_pipe should be non-blocking. In the meantime chromium.org has created a correction for this error: http://src.chromium.org/viewvc/chrome?view=revision&revision=177821 When will this correction be available in Firefox on linux?