As an improvement to the current global styles sidebar, @mtias suggested a good possibility would be implementing the following prototype, given that it is better than what we have now implemented in the repository:
https://g2-components.xyz/iframe.html?id=examples-wip-globalstylessidebar--default&viewMode=story#

So let us prioritize implementing this design.

This design can, of course, be iterated on.

The implementation of this design involves enhancing our components/bring some components/concepts from the G2 repository.

cc: @jasmussen,@jameskoster, @kellychoffman, @shaunandrews @youknowriad, @nosolosw, @ItsJonQ, @aristath, @mcsf

Related: #27331