This is seen in the "dutch" translated client:
in the chemical plant choosing window the [ Stookolie kraken naar Benzine ] option actualy says [ Smeerolie kraken naar Benzine ]
Just a minor traslation error.
[0.11.18] Dutch translation error
Re: [0.11.18] Dutch translation error
Translation bugs are fixed here: https://crowdin.com/project/factorio