Finding open paths in drawing

tl;dr: Is there an automated way to find broken/open paths as opposed to inspecting all lines at a high zoom level?

I have a drawing in LibreCAD which I import into OpenSCAD to visualize it as 3mm thick plate.  This flow has been working pretty well for me, specially since I can import specific layers and give each layer it's own thickness and placement.


After performing various modifications to the drawing in LibreCAD the cutouts in the drawing started appearing inverted with the part.  In other words, the paths in the drawing that are supposed to be cut-outs are showing up as solids, and then part itself doesn't show up.


This is the drawing in LibreCAD


This isn't the first time this occurs and the way I fixed it previously was by finding a broken path in the drawing (i.e. where to lines meet/corners) but I haven't had much luck finding the issue this time.

So my question is: is there a better way to find broken paths than to zoom in and inspect the whole drawing?