We've had an ongoing issue with missing vertical grid lines in our tree
stores. Finally was able to find time to isolate the issue.
If you use set_visible on various tree view columns, to hide certains
parts of the data, and then set grid lines for both or vertical on that
view, gtk will drop off a corresponding grid line for every previous
column that is hidden. We have a lot of hidden columns, for various
reasons, so we end up with only a few columns on the left having grids
and all the rest missing.
Haven't see any issue with the horizontal grids, probably because we
don't attempt to hide any rows, just columns.
Has anybody seen this? Any possible solutions, other than having to
rework thousands of lines of code to switch all the hidden columns to
the end of the array? (The latter is not an option at the moment).