Not exactly sure if this counts as a bug, but here it is anyway.
For some reason, the glass feature for tunnels have a condition that requires 2 other adjacent tunnels next to each other for it to work as intended. Not exactly sure why this is a thing, because I used a debug stick on a 1 long tunnel and it works just fine.

And to add onto this, when I use the debug stick to make the 1 long tunnel have the glass feature, I can disable AND re-enable the glass feature just fine using the wrench.
Please make 1 long glass tunnels possible, they seem to work just fine by using the debug stick.

Thank you for taking the time to read my ticket.

This issue has been marked as stale because it has been inactive for 3 weeks. It will be closed if it remains inactive for another 3 weeks.

This issue has been closed since it has been inactive for 3 weeks since it was marked as stale.

Just ran into this, I spent ~10 minutes trying to figure out how to add a window to a tunnel before realizing it was a bug / the description doesn't mention this as a requirement.