Adobe and Mozilla unable to fix Flash video crash problem
Adobe has as yet been unable to fix a problem which has left many Firefox users unable to watch Flash video online.
An update to the software - which is used by sites like YouTube - has been causing the Firefox browser to crash.
The problem was said to be affecting users of the browser on Windows Vista and Windows 7.
In a statement, Mozilla said: "Adobe and Mozilla are working closely to diagnose and address these issues."
It added: "In the meantime, Firefox users experiencing problems viewing videos in Flash Player should try the workarounds listed in this help article ."
Among the suggested solutions is downgrading Adobe's software.
The update was initially released on 8 June.
No other browsers or operating systems are believed to have been affected by the problem.