Found after a deeper search in the Internet at
http://kr.eguide.lgappstv.com/manual/w15_mr/dvb/Apps/w15_mr_e06/e_eng/share.html
Section Video Playback
Maximum data transmission rate:
Full HD
H.264 1920x1080@60P BP/MP/HP@L4.2 20Mbps
HEVC 1920x1080@60P MP@L4.1, Main10 Profile@L4.1 20Mbps
ULTRA HD Video [For ULTRA HD model only]
H.264 1920x1080@60P 4096x2160@30P BP/MP/HP@L5.1 50Mbps
HEVC 4096x2160@60P MP@L5.1, Main10 Profile@L5.1 50Mbps**
One more block below this is the list of supported codecs with details. I picked the important ones:
File Type: Codec support
MP4: H.264/AVC, MPEG-4, HEVC
MKV: MPEG-2, MPEG-4, H.264/AVC, VP8, VP9, HEVC
TS, MTS: H.264/AVC, MPEG-2, HEVC
Important information is in the top collection:
H.264 1920x1080@60P 4096x2160@30P BP/MP/HP@L5.1 50Mbps
HEVC 4096x2160@60P MP@L5.1, Main10 Profile@L5.1 50Mbps
From my understanding: this TV is able to playback only 4K UHD fullsize with 30 frames and HEVC with 60 frames.
Best would be to test what formats this TV is supporting by trial-and-error testing it. Personally, I use this website for downloading content in different formats / codecs (free to use, all are demo clips):
Demo UHD 3D
Be aware that some clips have huge file size.
4K streaming today is a the beginning of its career. The media players of TVs are not capable to stream every different format. I think, it’s better to test what the TV can play. Yet there are so many different codecs, some with 8-Bit, some 10-Bit, some H.264, H.265 or HEVC. Try it.