JNET helices drawn with notches when scrolling with a hidden column

Load an alignment with JNET annotation including helices and hide a column. Scroll left and right so that the helices pass outside the viewport and back in. The redraw of the helices looks like it has drawn the end multiple times so it has a notched appearance (see screenshot).

This does not seem to happen when there are no columns hidden so I imagine it is something to do with hidden columns.

Same issue with Secondary Structure annotation of RNA. E.g. load test.rnaml from the examples directory, hide some columns and scroll left and right. Blue arrows and orange arrows are redrawn with gaps.