a union of attributes first lit up 3 nodes, and later lit up 4 nodes

[terraswat]

A union of two attributes first lit up 3 nodes, and later lit up 4 nodes.

To reproduce:

• use CKCC/v1_nbl on production
• select KRAS and NRAS mutations
• do a union
• sometimes 3 nodes are lit up, sometimes 4

[mrJeppard]

No longer reproducible (after repeating 6 times).