Node and edge attributes lost in conversion to igraph

[mksteel]

This is similar to (or the same as) the issue previously posted

When converting a gexf to igraph the node and edge attributes are not retained. Example data used from previous issue: know_network_markup3.gexf.zip

When you read the data in with read.gexf you can see the node attribute "Modularity Class" that has integer data:

gexf_net <- read.gexf(file)

head(gexf_net)
gexf_net$atts.definitions

But that attribute is not linked to the nodes dataset of the gexf object

head(gexf_net$nodes)

When gexf is converted to igraph the "Modularity Class" node attribute is lost entirely

list.vertex.attributes(igraph_net)

The example data do not have edge attributes, but the same issue exists for edge attributes as well. Would appreciate any suggestions for how to extract/retain edge and node attributes when converting gexf to igraph