Ctrl-clicking with a tunnel tool to build a single tunnel entrance no longer works (i.e. not building a complete end-to-end tunnel). While holding ctrl, the tooltip correctly shows a build cost estimate for 1 tile, but then clicking has no effect.
This makes it impossible to build tunnels with curves, without using silly terraforming work-arounds/cheats.
This affects all tunnels, power, road and rail.
Introduced since r8874.
Actually introduced in r9416, and fixed in r9513 Thank you for reporting.
Confirmed fixed, thank you very much! :D