Quic is retransmitting huge packets when a big burst of packets is lost

[duncanmcl]

I tested a 5G network that sometimes loses connection drops bust of packets. When the client receives an ACK showing many packets lost in its SACK block, the client is sending all lost packets at the same time. I saw that Quic is trying to send huge packets like 140Kbytes by putting all lost frames to a single packet. Quic should limit the size of retransmitted packets to MTU and check congestion window. Otherwise they may be dropped in the physical layer or they will be fragmentted by IP layer. Quic RFC says that IP fragmentation is not allowed.