Created attachment 156946 [details]
Area dialog vs color picker drop-down

Currently the only way to create a custom palette is from Area dialog. But area dialog is not intuitive place to look for this functionality; most users meet colors more often using color picker drop-down. The drop-down is used on Format toolbar;  The drop-down resembles left part of the Area dialog; in Character properties (font color selection), in Line properties, border properties, etc.

Additionally, it's required to activate the Area dialog's Color button to access the custom palette controls. Users are confused finding it [1].

The proposal is to add the two buttons (Add/Delete custom palettes) into the picker. It has small enough height to accommodate the buttons (which additionally could be made small buttons with + and - to the right of the palette selector), and that would make this feature accessible.

[1] https://ask.libreoffice.org/en/question/223880