A Gantry cannot be deconstructed when Deconstruct Tool Filter is set to Building, or any other category aside from All.
A Gantry build order/outline cannot removed when Cancel Tool Filter is set to Building, or any other category aside from All.
All other Rocketry Buildings (rocket sections, telescopes, space scanners) can be cancelled and deconstructed when the Tool Filter is set to Building; the Gantry is the only exception.
Steps to Reproduce
See issue description. Likely something that can be fixed by assigning the Gantry to the appropriate category. Thanks!
This issue has not been confirmed by a developer yet.