Where is a filter to convert FrameMaker files on Linux?

(Paywall-free popularization like this is what I do for a living. To support me, see the end of this post)

Adobe FrameMaker is a “powerful authoring and publishing solution for technical communicators”. I used FrameMaker a lot from the mid 90’s until 4/5 ears ago and I have to say that I found it to be a great program, with a better, more productive interface than either Ms Office or OpenOffice. However, FrameMaker is a proprietary, really expensive product that doesn’t even run on Linux, so no matter how good it is it’s almost sure I won’t use it anymore.

The problem is that I still have on my computer several personal documents that I wrote and saved in FrameMaker format (.fmk file extension) in the 90’s, that is before I realized how badly proprietary file formats can impact economy, culture and personal stuff. Therefore, right now those files are just wasting space on my hard drive, even if I’d really like to access again some of them. I am sure there are many thousands of people in the same situation.

Who writes this, why, and how to help

I am Marco Fioretti, tech writer and aspiring polymath doing human-digital research and popularization.
I do it because YOUR civil rights and the quality of YOUR life depend every year more on how software is used AROUND you.

To this end, I have already shared more than a million words on this blog, without any paywall or user tracking, and am sharing the next million through a newsletter, also without any paywall.

The more direct support I get, the more I can continue to inform for free parents, teachers, decision makers, and everybody else who should know more stuff like this. You can support me with paid subscriptions to my newsletter, donations via PayPal (mfioretti@nexaima.net) or LiberaPay, or in any of the other ways listed here.THANKS for your support!