add css style when the dock is selected especially for multile dock existed

[Max-ChenFei]

Highlight the selected editor and graph editor for example increase width of the border. You can change the css class when replace the new editor and graph_editor

[Max-ChenFei]

Update the title on the tabbar and widgets both

[Max-ChenFei]

Example from jupyter lab

[drcd1]

I'm not 100% sure what you want... something like this?

[Max-ChenFei]

Please all commit the js file. I think we only care about the first level of tab and graph editor in the second level

[Max-ChenFei]

after #181