Hi Huseyin,
i tried your line of code with recent ConTeXt and luatex and i think it worked fine.
See attached files.

Greetings Lutz

Am 7. August 2018 08:29:10 MESZ schrieb "Huseyin Özoguz" <h.oezoguz@mmnetz.de>:
>I forget: I use now luatex beta 0.80.0 (and Context from 2015.04.15), 
>but the old pdf was compiled with luatex 0.77.0, is that the
>difference, 
>which deleted the footnote?
>
>(I hope this does not break the thread....never learned how to use 
>mail-lists with thunderbird)
>
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