After implementation and fixing the issue https://github.com/one-ware/OneWare/issues/112, it would now be possible to open the Nextpnr GUI for the GHDL/VHDL toolchain as well.
After implementation and fixing the issue one-ware/OneWare#112, it would now be possible to open the Nextpnr GUI for the GHDL/VHDL toolchain as well.