r Quarto subcaptions for more than 26 figures (HTML)

Add a JavaScript function that runs after the document loads that finds all subfigure captions using the class quarto-subfloat-caption and for captions beyond the 26th figure (index >= 26):

• Extracts the figure number
• Calculates the appropriate double letter (aa, bb, etc.)
• c Replaces the caption text with the new format

So:

Figure 27 will show as "(aa) Fig-aa"
Figure 28 will show as "(bb) Fig-bb"

---
title: "27Figures"
format: 
  html:
    include-after-body:
      text: |
        <script>
          // Function to replace figure subcaptions beyond 'z'
          document.addEventListener('DOMContentLoaded', function() {
            const subfigCaptions = document.querySelectorAll('.quarto-subfloat-caption');
            
            subfigCaptions.forEach((caption, index) => {
              if (index >= 26) { // Only process captions after 'z'
                const currentText = caption.textContent.trim();
                const figNumber = currentText.match(/Fig-([a-z]+)/i)[1]; // Extract the figure letter
                
                // Calculate the double letter (aa, bb, etc.)
                const pos = index - 25; // 27th figure starts at pos 1
                const letter = String.fromCharCode(96 + pos); // 97 is 'a' in ASCII
                const newLabel = `(${letter}${letter}) Fig-${figNumber}`;
                
                caption.textContent = newLabel;
              }
            });
          });
        </script>

---

Figure @fig-charts shows 27 subfigures.

```{r}
#| label: fig-charts
#| fig-cap: "Charts"
#| layout-ncol: 3
#| fig-subcap: 
#|   - "Fig-a"
#|   - "Fig-b"
#|   - "Fig-c"
#|   - "Fig-d"
#|   - "Fig-e"
#|   - "Fig-f"
#|   - "Fig-g"
#|   - "Fig-h"
#|   - "Fig-i"
#|   - "Fig-j"
#|   - "Fig-k"
#|   - "Fig-l"
#|   - "Fig-m"
#|   - "Fig-n"
#|   - "Fig-o"
#|   - "Fig-p"
#|   - "Fig-q"
#|   - "Fig-r"
#|   - "Fig-s"
#|   - "Fig-t"
#|   - "Fig-u"
#|   - "Fig-v"
#|   - "Fig-w"
#|   - "Fig-x"
#|   - "Fig-y"
#|   - "Fig-z"
#|   - "Fig-aa"

for (i in 1:29) { 
    plot(i, i)
}
```

As you can see, that works for more than 26 plots: