Problem displaying the euro symbol in hovertext in R plotly since 4.5

I have just installed the latest version of R Plotly (4.5.2), everything is great, just a little problem : if I try to make an html page with a plotly graph ncluding an hovertext with the euro symbol in it, previously, I just used the code € but it seems not to work. It’s surprising because there’s no problem if I look in the viewer of RStudio, but when I export the file in html and read it in chrome, it is not working (I see € instead of the euro symbol).

Here’s my code :

require(plotly)
require(dplyr)
iris %>% 
  mutate(hovertext = paste("Sepal.length : ",Sepal.Length,"K&euro;<br> Sepal.Width : ",Sepal.Width)) %>%
    plot_ly(x=~Sepal.Length,y=~Sepal.Width,text=~hovertext)

problem solved : the unicode \u20ac works fine.