Right now the upper selectable block in Designer View is <body>.
But for rem we need to edit the <html> tag's attributes.
Custom code is helpless here, we need to see changes immediately in Designer View.
Completely agree. rem's can be used in the designer but they are sort of useless if we aren't able to style the HTML element.
I use rem and I'd like to set html properties without having to resort to custom code too. @polina if you're using a custom code component from the Add+ menu, you'll see the changes in real time inside of the designer.
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