Since updating my browser to Firefox 35.0 last week, I've been getting bursts (dozens at a time) of identical error messages in my system log of the following character:

[0x0-0x7cd7cd].org.mozilla.firefox: ###!!! [Child][DispatchAsyncMessage] Error: (msgtype=0xAA0001,name=PTexture::Msg___delete__) Route error: message sent to unknown actor ID

Does anyone know what this means? Is it something to be concerned about (even though it doesn't seem affect Firefox's functioning)? Or is it just another 'insignificant' and annoying flaw in Firefox which will likely be fixed in the next iteration?