When I write redux framework option into header.php, it is shown.However when I add the same php code into a php file and include the php file from functions.php, it doesn't seem.
<?php global $redux_demo; ?> <?php echo wp_kses_post( $redux_demo['text-call-header'] ); ?>
include ( get_template_directory() . '/theme-color.php' );
theme-color.php contains same code above also global redux variable but it doesn't give any output.
as a smiliar second question, also I can't get output from my custom plugin when I include theme-color.php from my custom plugin.
$redux_demohasn't been defined yet. Normally you wouldn't echo a value directly from functions.php, so this is not a good way to test whatever you're testing. You should include the file inside a function that runs later.