Elliot Condon
Yes, we should be concerned. This is the biggest change we have seen in years and it will affect every website that updates to WordPress 5.0.

The new Gutenberg edit screen does not only change the way we edit the “post content”, it also changes the markup and elements on the edit screen. This is the change that makes me nervous for the WordPress community because so many of our content tools (plugins, themes, custom functionality) rely on these elements to exist.

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