Created attachment 201464 [details]
Example file from Word 2016

Attached example file from Word shows the interaction of the "Suppress line numbers" property in footnotes vs document body: 
When a paragraph style such as Footnote Text is used in a footnote, the lines are not numbered if line numbering is enabled for the document. This is weird as the style has the "Suppress line numbers" property disabled, meaning lines should be numbered. In Writer, they are indeed numbered.

When the same style is used in the document body, the lines are numbered in both Word and Writer.

1. Open a new Writer document
2. add some text, then a footnote
3. Apply the Footnote text paragraph style on the document body text (the attachment has this on the last two lines, 9-10).
4. On the Layout ribbon, go to Line Numbering and check Continuous
-> In the footnote there is no line numbering, in the document body there is line numbering
5. Save the file and open it in Writer
-> In the footnote there is line numbering

Version: 26.2.0.0.alpha0+ (X86_64) / LibreOffice Community
Build ID: 6faa7e6f7bae3e6a613b4f4b7cee4a9c6d2b7aae
CPU threads: 14; OS: Windows 10 X86_64 (build 19045); UI render: Skia/Raster; VCL: win
Locale: de-DE (hu_HU); UI: en-US
Calc: threaded

and in 3.3 already. 

Writer in a new document solves this by disabling the "Include this paragraph in line numbering" checkbox on the Footnote styles "Outline & numbering" tab.
On the other hand, this works consistently in the footnote and document body; unlike in Word. So changing the handling of the "Include this paragraph in line numbering" property at import time is not going to be a good solution.

To properly solve this, we probably need to implement a compatibility option.