### Bug description

I'm not sure if this issue belongs to `quarto` or `kableExtra`, but leaving the report here. Please let me know if this should be reported to `kableExtra`. 

Please see below for reprex. 

Edit: The issue is related to `pdf` output.
```
---
title: "test_quarto"
format: pdf
---
```
# Knitr
### Without label

```{r}
#| tbl-cap: "Example1"
#| tbl-subcap: 
#|   - "Cars"
#|   - "Pressure"
#| layout-ncol: 1

knitr::kable(head(iris))
knitr::kable(tail(iris))
```
Works fine

### With label

```{r}
#| label: tbl-example1
#| tbl-cap: "Example2"
#| tbl-subcap: 
#|   - "Cars"
#|   - "Pressure"
#| layout-ncol: 1

knitr::kable(head(iris))
knitr::kable(tail(iris))
```
Works fine 


# KableExtra

### Without label

It generates two additional empty labels: (a),(b),(c),(d)

```{r}
#| tbl-cap: "Example3"
#| tbl-subcap: 
#|   - "Cars"
#|   - "Pressure"
#| layout-ncol: 1

kableExtra::kable(head(iris))
kableExtra::kable(tail(iris))
```



### With label

```{r}
#| label: tbl-example4
#| tbl-cap: "Example4"
#| tbl-subcap: 
#|   - "Cars"
#|   - "Pressure"
#| layout-ncol: 1

kableExtra::kable(head(iris))
kableExtra::kable(tail(iris))
```
Works now.

Running on RStudio build 353 / R4.2.2


### Checklist

- [X] Please include a minimal, fully reproducible example in a single .qmd file? Please provide the whole file rather than the snippet you believe is causing the issue.
- [X] Please [format your issue](https://quarto.org/bug-reports.html#formatting-make-githubs-markdown-work-for-us) so it is easier for us to read the bug report.
- [X] Please document the RStudio IDE version you're running (if applicable), by providing the value displayed in the "About RStudio" main menu dialog?
- [X] Please document the operating system you're running. If on Linux, please provide the specific distribution.
cscheid
2023-02-23T22:19:32Z
matthewgson
bug crossref
v1.4
open
Subcaption issues with and without labels with KableExtra
https://github.com/quarto-dev/quarto-cli/issues/4517