I have just installed the new FW1.1 into my GH5 and it works a treat, it takes less than 60 seconds to perform. Make sure you insert the card into slot one.

FHD 4:2:2 10-bit video recording has been added. It can be selected in either FHD [MP4 (LPCM)] or [MOV] recording format.
4:2:2 10-bit video recording has been added to Anamorphic (4:3) mode.
There was a problem in which the exposure adjustment did not operate properly during live view standby when the [SS/Gain Operation] display was set to [ANGLE/ISO] while [Variable Frame Rate] was selected for Creative Video mode, this has been fixed.
A problem in [V-LogL] of Photo Style mode where afterimages appeared when recording video under high ISO sensitivity settings has been fixed.

Approximate available recording times for the motion picture settings added by this firmware update..

Get it here…

http://av.jpn.support.panasonic.com/support/global/cs/dsc/download/fts/index2.html