Bold First Word of Widget Titles

Got it!
Used this widget: https://www.ads-software.com/extend/plugins/linkable-title-html-and-php-widget/installation/

Still unclear on how to do it though for non-text widgets. Help?

Not sure if you still need this, but I was looking to do the same thing, and found this: https://www.brinzan.com/2012/01/wordpress-add_filter-for-widget-titles/

The span tags were stripped out of the post, and then again in my comment on the post. This is what should actually go in functions.php:

/************* FIRST WORD BOLD IN WIDGET TITLE *****************/

add_filter ('widget_title', 'wpzoom_fix_widgets');

function wpzoom_fix_widgets($old_title) {

    $title = explode(" ", $old_title,2);

    $titleNew = "<span>$title[0]</span> $title[1]";

    return $titleNew;

}

‘Course the span tags could easily be strong or em tags instead, whichever suits your purposes best.

Hope this helps ??