Opera

For Linux の PNG 問題で Yngve の説明 on opera.general

Since Opera also uses it's own PNG implementation on Linux the crash is caused by the same problem as on the other platforms. While Qt is able to use the system's libpng, this usage is outside Opera's control. Opera does not use Qt to decode and display PNG images. In any case Linux user's should patch their libpng package to avoid being attacked through other applications that does use PNG