If any html page uses an embed/object tag with the URL for the src/data attribute that has an unregistered protocol handler, the plug-in support code in the nsObjectFrame dies ungracefully. The end result is that none of the plug-in's methods are ever called. This becomes evident when you try to use any plug-in that uses it's own protocol streaming. Typically, these plug-ins will directly look up 'src' (or 'data') and then stream the data internal to the plug-in. For example: <EMBED type="audio/x-pn-realaudio-plugin" SRC="rtsp://www.some.server.com/g2video.rm" NOLOGO=true BACKGROUNDCOLOR=white MAINTAINASPECT=false WIDTH=200 HEIGHT=200 CENTER=true PREFETCH=true NOJAVA=true AUTOSTART=true CONTROLS=ImageWindow CONSOLE=display NUMLOOP=1> In this case, Mozilla doesn't know the 'rtsp' protocol and returns failure from NP_NewURI. But since the return value is never checked, the code continues as if everything was ok untill someone chocks on the null nsURI. What should happen, is that the plug-in should be treated as if no 'src'/'data' attribute was set, and let the plug-in code decide what to do.

I applied the patch.

verified that patch is in.