I am changing a theme in WordPress, and in an earlier theme, there was something like this that added a an email signup widget to the page:
[green_tick_1_list width="100%"]
But in the new theme that I installed, this just shows up as text. Is there any way to make it show up as the email signup form like it used to?
And what is that syntax? Is that something I can create in WordPress per each theme I use?
That’s a Shortcode.
It may be possible to find the function that renders that shortcode and copy/paste it into your own plugin, making it theme-independent, however, how easy that will be to do depends on how the shortcode works- if it depends on additional php functions, JavaScript, and CSS embedded within the theme.