[2.3.0] Checkmk Werk 16815 created: Missing piggybacked hosts

[//]: # (werk v2) # Missing piggybacked hosts key | value ---------- | --- date | 2024-05-10T09:28:11+00:00 version | 2.3.0p2 class | fix edition | cre component | checks level | 1 compatible | yes This fixes a regression in Checkmk 2.3.0 and 2.3.0p1. Piggybacked hosts containing invalid characters where dropped silently. This restores the original behavior: Invalid characters in host names are replaced by "_".