Filter "bereits adoptiert" should also show non adopted trees but in another color

[vogelino]

Background: Why this issue?

The filter"breits adoptiert" shows the engagement of the community on the platform but it could also help to choose for a tree to adopt that isn't yet adopted. For this purpose, all trees should be displayed and those that are already adopted should be highlighted.

Deliverables: How to fix the issue?

Show all trees and display them differently than those adopted (gray?)

Output: Gain of fixing the issue?

Helps to find a tree to adopt.

Issue creation checklist

• I have attached one of the priority labels HIGH, MIDDLE, LOW
• I have attached other labels with regard to the issues purpose (i.e.enhancement, bug, community feedback)