[4.9.0] GL-BE9300: link-down on one LAN port disables br-lan's only wired port (eth1.1), disconnecting all wired clients

Hi,

Thank you for the detailed report, troubleshooting information, and the workaround you shared.

We have reproduced the same issue locally on a GL-BE9300 running v4.9.0. We have recorded this issue and submitted it to the relevant team for further analysis.

If there are any further updates, we will continue to follow up with you in this thread.

Thank you again for your patience and assistance.