This is an old issue I reported in June 2018 that I was informed was fixed in QGIS 3. However, I am still having the issue in QGIS 3.2. I tried to find the closed issue #25977, but I cannot find it to ...

when pressing down arrow, the Layers panel will mark the current layer until I reach the 9th, aftwer that the marker disappears and don't sow the currently marked command. The layer details panel on ...