Styles with CSS variables in Connect static content macros are stripped - preventing some dark mode support

Issue Summary

First reported in The Developer Community. When applying any styles within the body of a static content macro, Confluence is stripping these styles before getting rendered in the page. This sanitization is performed for security purposes, however, in some cases this creates difficulty in the macro supporting Confluence theming.

This is reproducible on Data Center: No

Steps to Reproduce

1. Create a Connect static content macro
2. In the template for that macro, include custom `style` attributes with valid CSS markup

Expected Results

The provided `style` values are rendered within Confluence

Actual Results

Custom `style` attributes are stripped from the output and not applied

Workaround

Utilize a dynamic content macro which will render in an iframe from where the Connect app is hosted and has complete control over the styles being used