partly lost in some adjustments that were made to the submitted work,
which was focused on restoring the 'start installer' entry.
there is no need for dynamic setting of these two `source` imports in the
default file, in fact user modifications should also use the fixed import
commands in future.
note that the old placeholders however remain replaced, which inject
precisely this string, for backwards compatibility.
Gbp-Dch: Ignore
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