Hi, Juergen!
There is a custom module color palette setting (menu Module - Design settings - Colors tab). It is intended for quick access to predefined colors. If you define your custom colors here, then it will be saved for this module as a part of quick color palette. Quick color palette is available as a drop-down menu by clicking a small arrow near the Fill color icon (or Line color icon).
Unlike usual Windows color picker (which loses settings sometimes - you're right), colors should not disappear from this palette, because it is saved as module setting.
Hi, Juergen!
There is a custom module color palette setting (menu Module - Design settings - Colors tab). It is intended for quick access to predefined colors. If you define your custom colors here, then it will be saved for this module as a part of quick color palette. Quick color palette is available as a drop-down menu by clicking a small arrow near the Fill color icon (or Line color icon).
Unlike usual Windows color picker (which loses settings sometimes - you're right), colors should not disappear from this palette, because it is saved as module setting.