How change background color of the mail datagrid?

In trying to change the background color of the email listings (I think it is called the datagrid) I went to menu/tools/theme editor/datagrid/background, changed the color selection/apply. The color changes in the command picture, but not in the actual email listing. How do I change the theme mail listing background color?

domingo 06 marzo 2022 :: 1820hrs (UTC +01:00)

Carry out the changes you want to make then you need to SAVE AS (top left drop down in Editor)
Give your Theme a name such as the original Theme name with _1, then import this new Theme at:
Menu ->Settings ->Appearance ->Themes ->Import ->Apply ->OK

¡Saludos desde la soleada Sevilla en España!

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