fix: styling of draganddrop layers

[jokd]

Fixes #1764, alternative solution to #1765

[Grammostola]

Looks good to me. Neat solution, make the viewer aware of the style, works well in print and after (legend too if less [234, 234, 17, 1] like in my example in the issue and more 'rgba(234, 234, 17, 1)' and makes sense as viewer.addLayer is now employed. Well done

[jokd]

Looks good to me. Neat solution, make the viewer aware of the style, works well in print and after (legend too if less [234, 234, 17, 1] like in my example in the issue and more 'rgba(234, 234, 17, 1)' and makes sense as viewer.addLayer is now employed. Well done

I made an issue for that since it's not related to this.