New idea

[Jb10]

We should be able to upgrade more than one wall at a time, so If you press select row on the walls then you can press upgrade all walls

[Siddmaster]

This idea should go in ideas and feature requests, also it is ruled out, since I am officially too lazy to explain why this is ruled out I advise you to read the sticky on ruled out requests in the ideas and feature requests forum.
This is a creative idea, but read the stickies before posting again.
Good day.