Pylon GP-20 is disappeared when entering a scene

[OliverWieland]

I want to build a tank farm on Minmus. So I attached a GP-20 to the surface near my Convert-o-tron and connected them. When I leave the scene, for instance go to the Tracking station and come back, the GP-20 is disappeared.
As you see in the screenshot, after attaching the GP-20, it seems that it's floating (Attchached with H + LMB). Don't know if that is a problem.

Kubuntu 24.04.
KSP 1.12.5.3190 (LinuxPLayer)
KAS 1.12 (installed with CKAN 1.34.4)