Oversized EBML headers for WebM live stream
From version ffmpeg 4.1 or above, when trying to stream WebM video Icecast produce error: EBML Header too large, failing
Solution is to increase EBML Header in format_ebml.c
from 131072 bytes (0.125 MiB) to bytes 524288 (0.5 Mib)
Change in https://gitlab.xiph.org/xiph/icecast-server/-/blob/master/src/format_ebml.c from #define EBML_HEADER_MAX_SIZE 131072
to #define EBML_HEADER_MAX_SIZE 524288