We should try to use split buttons for all toolbar color choosers, for a longer
rationale, see: bug 45671.
How to get to see the button:
* Open Calc
* In the Formatting toolbar, find the Font Color item (icon: an "a" with a colored line below it)
See that the button is a simple button, not a split button.
Winfried Donkers committed a patch related to this issue.
It has been pushed to "master":
fdo#45688: Split button for Calc cell font color
Great stuff, Winfried! Thank you!
transparent colour is a choice in the palette, but the cell background does not get transparent. That'll have to be fixed, so I reopened the bug.
fixed under bug 45671
*** Bug 38810 has been marked as a duplicate of this bug. ***