LVS browser crashes

[klayoutmatthias]

See this post for details: https://www.klayout.de/forum/discussion/2211/klayout-0-28-was-crashed-when-click-on-netlist-database-browser#latest

[klayoutmatthias]

The root cause of this crash is destruction of the reference netlist by the LVS script when the variable goes out of scope. The reference netlist needs to be kept inside the LVSDB object rather than owned by the Ruby interpreter.