Drop down list of posts from a category

Hello,

I am using the Vantage Premium Version: 2.3.3 By SiteOrigin theme, with a latest version of WordPress.

All my plugins are updated, all is clean, very few content for now, just dummy-texts and photos. I am currently setting up the theme, customizing everything on a child theme.

I would like to create a widget that is a drop-down of all posts from a single category, OR a collapsible list of the same category, ordered by the time they are posted.

I have tried the solution described here: , but it just renders my website blank & tells me there’s a parsing error in the functions.php file.

“Parse error: syntax error, unexpected ‘<‘ in wp-content/themes/vantage/functions.php on line 420”

This is odd, since line 420 is above the lines I am adding in.

Anyway, any help is appreciated: a plugin, a solution I can work with some other way, etc.

Thank you,
Alexa