[suggestion] Show/hide all layrrs

[Shohreh]

Hello,

Unless I missed it, the application doesn't allow the user to show/hide all layers in one go.

Cheers,

[yohanboniface]

cc @Aurelie-Jallut, to add in the new layers box ?

[Hedaja]

I support this enhancement. I'm working on a birding project at the moment and I therefore have about 50 layers. A hide/show all button would be quite time saving when trying to look at a specific layer.