Cross-referencing for images or tables via \@ref(tab:xxx) looks like working only under, say, bookdown::html_document2.
However, previewing the output by clicking "Open Preview to the Site" does not render cross-reference properly.
For example:
---
title: "R Notebook"
output:
bookdown::html_document2: default
---
{r table1}
knitr::kable(mtcars[1:5, 1:5], caption = "The mtcars data.")
`mtcar` data is shown in Table \@ref(tab:table1).
The vscode-R preview results in

The correct one with rmarkdown::render or Ctrl + Shift + K results in

The current keybinding to open preview is Ctrl + Shift + V, is it possible to change it to render and open the preview with Ctrl + Shift + K, just like in RStudio?