ggplot latex issues for R Shiny apps when published

Hi -- I've been running into issues with Latex in my ggplots for Shiny apps when they are published. Locally, the Latex compiles fine, but when I publish the app, the Latex is incorrect. Specifically, anytime there is a sort of "container" (e.g., a tilde or bar) over a Latex symbol (not text), the container overlaps with the symbol, instead of being over it. This issue persists with both expression() and latex2exp:TeX(). Reprex below:

# Packages ----

library(shiny)
library(ggplot2)
library(dplyr)
library(tidyverse)
library(latex2exp)
library(plotly)

# Loading data ----

df <- as.data.frame(iris)

# ui.R ----

ui <- fluidPage(
  withMathJax(),
  fluidRow(
    column(12,
           "Hello"),
    plotOutput("plot")
  )
)

# server.R ----

server <- function(input, output){

  output$plot <- renderPlot(

    df %>%
        ggplot() +
        aes(x = Sepal.Width, y = Sepal.Length) +
        geom_point() +
        labs(title = expression("Title is " * widetilde(beta)))
  )

}

# Run the app ----

shinyApp(ui = ui, server = server)

Local version:

Published version:

This also appears to be an issue across browsers, as I've tried in both Safari and Chrome.

Any help would be appreciated!