public void setExtraDefaults( Map<String, String> extraDefaults ) {
		this.extraDefaults = extraDefaults;
	}
Sets extra UI defaults, which are only used when setting up the application look and feel.
E.g. using {@link UIManager#setLookAndFeel(LookAndFeel)} or {@link #setup(LookAndFeel)}.
<p>
The extra defaults are useful for smaller additional defaults that may change.
Otherwise, FlatLaf properties files should be used.
See {@link #registerCustomDefaultsSource(String)}.
<p>
The keys and values are strings in same format as in FlatLaf properties files.
<p>
Sample that setups "FlatLaf Light" theme with white background color:
<pre>{@code
FlatLaf laf = new FlatLightLaf();
laf.setExtraDefaults( Collections.singletonMap( "@background", "#fff" ) );
FlatLaf.setup( laf );
}</pre>

@see #setGlobalExtraDefaults(Map)
@since 2
flatlaf-core/src/main/java/com/formdev/flatlaf/FlatLaf.java