Feature Request: Separate multiple footnote symbols with a comma

[NourEdinDarwish]

Thank you for the wonderful flextable package.

I would like to suggest a minor enhancement to how multiple footnote references are displayed in a single cell. Currently, the reference symbols appear adjacent to each other without any separator (e.g., ¹²).

For improved clarity, it would be beneficial if these symbols were separated by a comma (e.g., ¹,²). This is the default behavior in the gt package and makes complex tables easier to read.

library(gt)
library(flextable)

# add footnote to a table
# flextable way
head(iris) |>
  flextable() |>
  footnote(
    i = 1,
    j = 1:2,
    value = as_paragraph("This footnote 1"),
    ref_symbols = "1",
    part = "header"
  ) |> 
  footnote(
    i = 1,
    j = 1,
    value = as_paragraph("This footnote 2"),
    ref_symbols = "2",
    part = "header"
  ) 

# gt way
head(iris) |>
  gt() |>
  tab_footnote(
    footnote = "This footnote 1",
    locations = cells_column_labels(columns = c(Sepal.Length, Sepal.Width))
  ) |>
  tab_footnote(
    footnote = "This footnote 2",
    locations = cells_column_labels(columns = Sepal.Length)
  )

Sepal.Length1,2	Sepal.Width1	Petal.Length	Petal.Width	Species
5.1	3.5	1.4	0.2	setosa
4.9	3.0	1.4	0.2	setosa
4.7	3.2	1.3	0.2	setosa
4.6	3.1	1.5	0.2	setosa
5.0	3.6	1.4	0.2	setosa
5.4	3.9	1.7	0.4	setosa
1 This footnote 1
2 This footnote 2

^{Created on 2025-09-04 with reprex v2.1.1}

[davidgohel]

see argument inline and sep in footnote

The second example shows something very close (you should change sep)

https://davidgohel.github.io/flextable/reference/footnote.html

[davidgohel]

I see sorry my misunderstanding

I don't think it's hard but note footnote() can be replaced by a combo of append_chunk() and add_footer_line() where you are free to format things the way you want