MacBoeck

That works. Thank you. But because it is a workaround I thought it was worth posting here as an idea for future updates. But really - thank you anyway!

Aha. I see, what that's doing! But: it lets me view and do something to that single layer. But what I meant is un-checking all other layers but one (for export for example). That's why I kept clicking on the checkbox with some modifier keys.

That is not working for me?! Neither directly on the checkbox nor on the layer area / name. What am I doing wrong?

(Maybe I'm not finding it, then it is overly complicated and that's to be addressed.) But I'm missing the possibility to do such: if you have multiple layers and all are visible you can click on the little checkbox on the right to make that one layer invisible. But sometimes you want to see only the one you are working on. Instead of clicking 100 layers invisible there could be the option (like in other pro music software for example) to alt-click (or some other modifier key) to de-view all layers but the one the click was made on.