How do I add R inline a code within a quarto figure subcaption

In quarto, I a trying to add inline code within a figure subcaption, I have tried several things but none seem to work. Below is a reproducible example:

test=403.87

#| label: example
#| code-fold: true
#| fig-show: "hold"
#| layout-ncol: 2
#| fig-cap: !expr "paste0('R expression in the caption works: ',test)"
#| fig-subcap: 
#|   - !expr "test" 
#|   - !expr "paste0('R expression in the subcaption does not work: ',test)"

library(ggplot2)
ggplot(airquality, aes(Temp, Ozone)) + 
        geom_point() + 
        geom_smooth(method = "loess", se = FALSE)
ggplot(airquality, aes(Temp, Ozone)) + 
        geom_point() + 
        geom_smooth(method = "lm", se = FALSE)

This is not supported in fig-subcap. The quarto developers recommend this approach instead:

---
title: "Test"
format: html
---

```{r}
#| echo: false
test=403.87
```

:::: {#fig-test layout="[1,1]"}

::: {#fig-test-1}
```{r}
#| echo: false
plot(1:10)
```

`{r} paste0('R expression in the subcaption works too: ',test)`
:::

::: {#fig-test-2}
```{r}
#| echo: false
plot(1:10)
```

`{r} test`
:::

`{r} paste0('R expression in the caption works: ',test)`
::::

Which produces this output: