Layer jumped out suddenly it's upper level by left mouse click

I have a very strange problem for layers. A few times when I click left mouse on the name of a sub-layer to make this layer on/off. It jumped out suddenly its upper level (Move Up One Parent). The problem comes very often but I don’t quite understand what I did with the left mouse. So I have to drag it back under its layers parent every time. Thank you very much for your help.

Hi -

If a nested layer is at the bottom of the list, a small click-and-drag downward will move the layer to the top level. If that’s not the issue, we’ll need more information on how to reproduce the issue.
-wim

When the list of sub-layers is very long, it is not easy to return the jumped sub-layers to the initial position by click-and-drag. But it does not matter, I would like to understand why the layer is jumped out, I tried to reproduce that with any type of click but without success. This problem happens often unintentionally. If it’s not a known Rhino operation, maybe I’ll change my mouse to see if it’s because of the mouse

Hi -

It’s not a known Rhino operation, no.
-wim

Thank you very much for your very quick response