Issue #2559961 by angrytoast, Krzysztof Domański, drup16, Lendude, vasike,...

Issue #2559961 by angrytoast, Krzysztof Domański, drup16, Lendude, vasike, Leksat, sam711, tar_inet, mlncn, JordiK, adinac, Pascal-, joshua.boltz, froboy, oriol_e9g, alison, codesmith, luenemann, specky_rum, daffie: ManyToOneHelper ignores group configuration for some cases

(cherry picked from commit aec9cf8c)