If you don't actively close the controls HUD in the adventure mode it will still show up e.g. if you go into the sandbox, and becomes impossible to close.
Steps to reproduce
Start fresh, open the adventure exploration mode, exit out of it straight away without closing the controls HUD, open sandbox.
Principia version
latest
OS / Hardware
Desktop
Summary
If you don't actively close the controls HUD in the adventure mode it will still show up e.g. if you go into the sandbox, and becomes impossible to close.
Steps to reproduce
Start fresh, open the adventure exploration mode, exit out of it straight away without closing the controls HUD, open sandbox.