I just tried to use $custom_tax_mb->set( 'force_selection', true ); with radios and was surprised by the behavior to the point that I'm not sure it's right.
When $force_selection is set to false for radios, a hidden "None" option is added. When true, that option is gone but there is still no default selection of the first taxonomy term. I expected that the behavior would be more like the select implementation where the first option is defaulted to when $force_selection is true instead of a "none" option.
As it stands, I don't think $force_selection actually results in any difference in the post's term assignment when using radios.
I just tried to use
$custom_tax_mb->set( 'force_selection', true );with radios and was surprised by the behavior to the point that I'm not sure it's right.When
$force_selectionis set tofalsefor radios, a hidden "None" option is added. Whentrue, that option is gone but there is still no default selection of the first taxonomy term. I expected that the behavior would be more like theselectimplementation where the first option is defaulted to when$force_selectionis true instead of a "none" option.As it stands, I don't think
$force_selectionactually results in any difference in the post's term assignment when using radios.