Cannot connect compatible liqids

[tomppa]

Version 1.1.x , x >= 15 - don't know how to figure out precise version - game refuses to tell (hint: version menu would be helpful)

Issue:
Want to connect tubes containing the same liquid (liquid gas), but game refuses, claiming being incompatible

Expected behaviour: can put tube connecting same liquid

Current behaviour: game claims liquids are incompatible

Hint: Game was started in 1.0.0 stable, and continued in whatever version was current on Dec 30, 2020 - don't know how to establish precise version.

Saved game available on request.

[MassiveDynamic]

You have different liquids in the pipes. Use the red x to drain the fluid from the pipes or remove them and replace them.

I know that you are saying to yourself “NO I DON’T” but, yes ... you do. Follow my instructions and it will work.

[picklock]

The version you are playing is shown in the top right of the menu screen or after klickoing the abaout button in the main menu.

[tomppa]

Thanks to both of you. Will try!