I use the Toradex Yocto distribution with a Verdin IMX8-MM and it seems that TCP Windows scaling option is not send in SYN packet even if it’s enabled.
I have configured : net.ipv4.tcp_window_scaling = 1
And my socket receive buffer size is greater than 65 K :
Even with standard command like wget, I never see the TCP windows scale option.
On my laptop if I use wget, I can see in Wireshark that TCP windows scale is announced.