String with value of 'empty' is being translated by translate pipe to [Object object]

[Lavos96]

Current behavior

String with value of 'empty' is being translated by translate pipe to [object Object]
for example
{{ 'empty' | translate }} results in [object Object] in template

Expected behavior

String with value of 'empty' should be translated by translate pipe normaly (in that case it should return 'empty')
for example
{{'empty' | translate }} results in 'empty' in template