Thanks for your comments and suggestions!
Especially onpon4's, ADFENO's and strypey's points made me reconsider my role
in this software issue and I decided to write to the technical support team.
You will find a translation of my inquiry below.
Please note that I'm not in the US and I'm not applying to a US funding
organization but with the DAAD, the German Academic Exchange Service.
This is my inquiry, and I'll let you know about responses.
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Dear Sir or Madam,
Recently I applied for a DAAD grant. In doing so, I encountered serious
problems with handling the "DAAD general application form."
This PDF document can be opened and edited with Adobe Reader only, according
to your technical documentation and according to my experiences. However,
this software is no longer available for me as a GNU/Linux user. (Development
and support for Linux were dropped in 2013.) Each of the PDF applications
available to me displayed the following error message: "To view the full
contents of this document, you need a later version of the PDF viewer. You
can upgrade to the latest version of Adobe Reader from
www.adobe.com/products/acrobat/readstep2.html For further support, go to
www.adobe.com/support/products/acrreader.html" I suspect that some feature of
Adobe's Digital Rights Management is activated in this application form which
prevents editing with other software.
Eventually, I could not find a way to apply for one of your grants using my
GNU/Linux system. In order to submit my application, I had to use a Windows
system of somebody else twice. This took me about three hours longer than
without this issue.
I assume your intentions are not to exclude us GNU/Linux users from
applications with your institution. However, such applications are quite
difficult for us and need more time, and depend on other people's computers.
I think this is unjustified. Do you see any possibility to create your PDF
forms and documents in such a way that theyw can be edited by GNU/Linux users
in the future?
Best regards
[name, address]