Honestly, the City of Montgomery needs to update its instructions and it FAQ.
As Critter-3 implies, Schedule 1 will not always print, because there are plenty of taxpayers who would have no entries on that form.
The FAQ on the City website states "(attach) a copy of the front page of the Federal 1040 Form, including all federal schedules that per...".
This is, of course, hopelessly out of date, since it refers to lines on the 2017 1040 (these lines changed in 2018 and again in 2019). The point of it was to ask you to add any forms that refer to Schedule C, Schedule E, Schedule F, or Other Income.
The instructions you quote ("Copies of all W-2 forms, page 1 of the Federal 1040 form, and Federal Schedule 1. If applicable, please submit all supporting Federal Schedules for income shown on Lines 3, 4, 5 and 6 of the Federal Schedule 1 form (i.e., Schedule C, Schedule E, Schedule F, and Form 4797") have the same intent, but fail to address the situation that you might not have any of these income items so don't have or need a Schedule 1.
I am willing to bet that if you called the City Income Tax Office at
Phone: (513) 792-8333
Fax: (513) 891-2994
Email: tax@montgomeryohio.org
that they would tell you to skip the Schedule 1 in your case.
However, if you don't want to wait until Monday, then do as Critter-3 says and just add a blank Schedule 1 to your return.
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