LibreOffice can also import a pdf file creating a new .odt file.
The only problem is that it creates new format types for every page which is a pain to fix up but by specifying revised styles specs for all such as Header, 1, 2, 3 etc, Paragraph, text body for font & size, etc., it does not take so long.
Judging by the amount of work that I have been getting over the last 5 - 10 years and despite being 'retired' Cobol is alive and well.
This applies to both m/f (mainframe) and work on PC / servers much of which uses Gnu Cobol.
Cobol programming people will be needed for a long time yet - why ? well the old saying seems to still apply - If it isnt broke don't fix it.
As can be testified by by the number of sites that have been advised to move away from both Cobol and kit from mainframe to PC/servers to language x only to continue with existing (admittedly with updating) having been very bitten, both by escalating costs and poorly designed and written replacements).