Seeing red-colored stuff as blue in YouTube videos? Adobe Flash Player on Fedora seems to mess with settings, here is quick fix.
CentOS users might have problems with WLAN on their laptops especially with BCM4311 802.11b/g WLAN chipsets. These can be solved by installing proprietary Linux driver by Broadcom.
Virus spreads via video posted on Facebook! Video named "Mlada ceska pred webkamerou ukazuje vse!" is already blocked by ESET, some info was published by Kaspersky.