Flextable header is not repeated in each page for figures with captions

Bug description

If a table has no caption, its header will be repeated in each page. But if it has a label, the header is not repeated.

Taken from Stack Overflow.

Steps to reproduce

---
title: "My document"
format:
  docx:
    colorlinks: true
---

```{r}
#| label: tbl-test
#| tbl-cap: Table caption
flextable::flextable(iris)
```

Expected behavior

```{r}
---
title: "My document"
format:
  docx:
    colorlinks: true
---

```{r}
#| tbl-cap: Table caption
flextable::flextable(iris)
```

Actual behavior

Your environment

• OS: Windows 10
• IDE: RStudio 2024.09.1

Quarto check output

Quarto 1.6.39
[>] Checking environment information...
      Quarto cache location: C:\Users\myusername\AppData\Local\quarto
[>] Checking versions of quarto binary dependencies...
      Pandoc version 3.4.0: OK
      Dart Sass version 1.70.0: OK
      Deno version 1.46.3: OK
      Typst version 0.11.0: OK
[>] Checking versions of quarto dependencies......OK
[>] Checking Quarto installation......OK
      Version: 1.6.39
      Path: C:\Users\myusername\AppData\Local\Apps\Quarto\bin
      CodePage: 1252

[>] Checking tools....................OK
      TinyTeX: v2024.01
      Chromium: (not installed)

[>] Checking LaTeX....................OK
      Using: TinyTex
      Path: C:\Users\myusername\AppData\Roaming\TinyTeX\bin\windows\
      Version: 2023

[>] Checking basic markdown render....OK

[>] Checking Python 3 installation....(None)

      Unable to locate an installed version of Python 3.
      Install Python 3 from https://www.python.org/downloads/

[>] Checking R installation...........OK
      Version: 4.4.1
      Path: C:/Users/myusername/AppData/Local/Programs/R/R-4.4.1
      LibPaths:
        - C:/Users/myusername/[projectDirectory]/renv/library/windows/R-4.4/x86_64-w64-mingw32
        - C:/Users/myusername/AppData/Local/R/cache/R/renv/sandbox/windows/R-4.4/x86_64-w64-mingw32/b05f06b7
      knitr: 1.49
      rmarkdown: 2.29

[>] Checking Knitr engine render......OK