If you haven't, you can install & try it out for free from Atlassian Marketplace https://marketplace.atlassian.com/apps/1219685
If you have already used Code Macro, it works in similar way.
Once installed, go to your Confluence page & follow these steps.
{
& click on Open macro browser
Insert
edit
and then preview
on the right side to view highlighted code. If everything is fine, save and publish.That's all. You can now use syntax highlighting for code written in any programming language.
If you face any issue, please create an issue on Github https://github.com/chhantyal/code-syntax-highlighter/ or send me an email.
nkchhantyal [at] gmail.com