Superposed plugins

[apprenti-sorcier]

In QGIS, it’s easy to drag and drop side panels so that you save some space.
For example, I superpose the Layers and Explorer side panels. I also superpose Zoom level plugin and Lat Lon Tools, because I rarely need them at the same time. See this screen capture.

The former stay stacked after a QGIS restart. However, the latter don’t.
Since we worked on the persistence of the panel in the previous issue, can you also check why this panel doesn’t stay on top of others after a restart if its custom position has been stacked?
Thanks in advance.