I use the panel in auto-hide mode from the left side of the desktop. This combination makes the panel continuously hide and show when the mouse is pressed against the left desktop boundary. 1. Dock the panel to the left in auto-hide mode. 2. Leave the mouse pressed against the left desktop boundary. The panel hides and slides back in continuously. Not to be confused with flickering. This doesn't happen if the panel is docked to the top, right, bottom. Linux/KDE Plasma: Neon 18.5 KDE Plasma Version: 5.18.5
*** This bug has been marked as a duplicate of bug 397175 ***