Font colors missing after upgrade to LO

When I open existing docs or spreadsheets the toolbar font options (font colour, background & highlight) have lost the individual colour squares.
Drop down is still defaulted to ‘Standard’.
Area below is now white spaces - it used to show all the main colours available.
‘Recent’ box was empty to start but is populated if a colour is used.
Custom colour option is still working.
How do I recover the colour squares?

It could be a problem with the drop down list as it contains 2 entries for ‘Standard’. The first entry has no colours, but the second entry has a full set of colours.