Prefix DOM element classes to avoid CSS collisions

[tomichal]

This is an issue originally opened here: GrapesJS/grapesjs#471
I created a patch with a fix ready to be pushed. How can I contribute it?

[artf]

Thanks @tomichal you can send a PR of your fix on this repo

[tomichal]

Thanks @artf, just created #3

[artf]

Merged #3 👍