- Styling the "required star" is theming (i.e. not a custom style for a single app) so it should be handled by the Vaadin theme styles (UI). I added it our form.scss and will push it shortly.
- The problem with @Stylesheet annotation is that 1st it will download/append a new CSS file; then such generic CSS rules might apply as well to other unwanted places in the admincentral. For custom app styles we also have app theming (tentatively encourages to scope the styles with the app-[mytheme] parent selector) but it doesn't apply here.
- Then get rid of the WorkspaceComboBox class, use a vanilla ComboBox instead, we're not augmenting the component with generic widget capabilities.
- Finally you may also do it in tools modules O

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