%% Trailer seems not supported

[fxf06]

Description

FSyacc ignores code after the last %%

Repro steps

Write a single grammar and add %% at the end and some code.

Expected behavior

I would expect, like with ocamlyacc, to have the added code in the generated code

Actual behavior

The code added in the trailer does not appear

Known workarounds

Wrap my parser in an other module.