Leaflet Map not rendering in Rmarkdown, R Notebook when opened in browser

Question

For some reason, I can view the leaflet map in the RStudio viewer, but not in a browser, even a very basic map.

```{r, echo=FALSE, warning=FALSE}
library(leaflet)
m <- leaflet() %>% addTiles()
m
```

All other images appear no problem when viewing the HTML file in the browser, but the map won't. Anybody run into this problem before?

Answer 1

There is something wrong with the default tiles set. Try this:

```{r, echo=FALSE, warning=FALSE}
library(leaflet)
m <- leaflet() %>% addTiles(urlTemplate = 'http://{s}.basemaps.cartocdn.com/dark_all/{z}/{x}/{y}.png')
m
```

You can find a good resource here for alternative third-party tiles.