This is about both editing and exporting PDFs.
The attached PDF has an explicit explanation of the issues + screenshots. Text from the attached file goes right here.

I’ve got Adobe Acrobat Pro DC 2015 Release Version 2015.006.30355.

On Web page https://www.zm.gov.lv/mezi/statiskas-lapas/nozares-informacija/buklets-meza-nozare-latvija-?nid=1088#jump
..there is a link to a PDF file "Latvia's Forests During 20 Years of Independence" 2010, https://www.zm.gov.lv/public/ck/files/ZM/mezhi/buklets/MN20EN.pdf
The PDF file seems to be a nicely composed PDF with Adobe InDesign CS5.5 (7.5.2).
The font used, Museo Slab is a publicly available font, I bet it should not have any major issues.

In the said file, page 47 there are multiple issues with a context having a ligature ffi in the source text ‘office’. This is the only occurrence in the file containing the word ‘office’.

1. When Copy/Paste is applied from Acrobat Pro to Notepad++ with the regular Select tool, I get C2 8A UTF-8 bytes which is shown as [VTS] in Notepad++.

No ‘office’.

1. With Text Edit tool (Tools > Edit PDF > Edit) I cannot select the entire word. Only starting from the second letter. I try to do selection both with mouse and with SHIFT+keyboard arrows. No way to select the first letter. BUT as for the remaining letters, I get all the components of the ligature as correct letters in the output with Copy/Paste to Notepad++:

Just ‘ffice’ of ‘office’.
But this shows that there is facility to get normal text from ligatures, however it is not implemented correctly or not at all in all the tools and scenarios making them all buggy. Why can I not select the leading ‘o’?

1. Also, when exported to HTML, the ligature gets encoded as C2 8A in UTF-8.

The same as for Copy/Paste.

If the routine which allows copying ffi from the edit tool was applied to Select and Export tools, some of the Acrobat Pro bugs would be fixed.

I have several other bugs in my list. If this makes sense for Adobe, please confirm, and I will keep posting. Moreover, I hope these will be fixed asap. These bugs are there since at least v9.

Within the Adobe Admin Console an administrator does not have the capability to export user data identifying which product is assigned to the user. To run the reports you have to drill to every product and export the data. I asked for the report from tech support and they said the feature I am requesting is not available but to request to it added as a feature. On the feature wish form drop list it does not specify Admin functions so I chose first Adobe product on the list. The function to export all user data to understand the products purchased and who they're assigned to should be available to customers and to not have it or be willing to produce it is unacceptable customer service.

I can see certain documents were created in MS Word with simple follow on/flowing text and standard paragraph styles ie no **** text boxes. Even with the export options turned off, Acrobat does this incredibly annoying export to text boxes where it is simply run-on (flowing) text. You then have to extract the text, box by box to get the document to be in an editable form. Even exporting to rtf has similar issues. Exporting to plain text means you have to format.

In the end, you waste valuable time either extracting the text or having to reformat the text to get something that's useful

Steps to Reproduce:
1. open acrobat DC
2. create a PDF from file.
3. save file
4. check the original file to see if it has retained it's format and is properly openable.

Environment:
OS: Windows 10
CPU: Intel i5 6600k @4.3GHz
RAM: 16gb(2x8gb) G-skill Trident-z @3000MHz
Motherboard: Gigabyte G1 gaming 5

Acrobat Version: 2015.023.20070

Expected result:
Doing this should bring up a new save dialogue, or the save-as dialogue technically. Then once it is saved it should switch to that file.

Observed Result:
Doing this overwrote the original file w/o providing a save dialogue.

I have attached the ruined file and a SysInfo Report from acrobat.

When exporting a PDF to an HTML, DOC or DOCX, ACROBAT DC and also ACROBAT 11 PRO, looses/converts the numbers at the beginning of the row which contains . and 000 (00).
For example, in word, the number 15.000 becomes a numbered list starting with "15.1" and in HTML becomes the same or disappears completely. This is a very frequent problem, in 100 pdf's 85 of them have this problem on multiple pages.
Considering that we work with ACROBAT PRO and DC with almost 10000 of pdf's monthly (from 2006) for us is a very serious problem that we have every day.
Because of GDPR, I can't put the whole document or the PrintScreen with all the data from pdf. But I marked the situation in the print screen and if needed, I can provide pdf's it the confidential data is preserved.

We all use:
Windows 10
ACROBAT DC version 2019.021.20061
ADOBE Acrobat XI 11.0.23