When moving or resizing the "Desktop Sticky Notes" widget such that it would be off the right-hand side of the screen, it will jump to the left side of the screen when releasing the mouse.
Can reproduce this bug in: Distribution: KDE neon Developer Edition - Stable Branches Plasma: 5.11.4 Frameworks: 5.41.0 Qt: 5.9.3 Kernel 4.10.0-40-generic Type: 64-bit
Yeah, this has been fixed.