Fix missing member variable reference
Fix missing member variable reference

Bug caused last commit: https://github.com/dainst/arachnefrontend/commit/49f2facdd5ec5c11e30f291192e85cfd1e6975ba

codarchlab/arachnefrontend,codarchlab/arachnefrontend,dainst/arachnefrontend,dainst/arachnefrontend