How to prevent a shiny app from being grayed out?

Question

we have a shiny app hosted in Heroku. After 55 secs of user inactivity, the app will be grayed out. This is applicable for Chrome and Safari. Edge is working fine. Heroku ha

Answer 1

After 55 secs of user inactivity, the app will be grayed out.

I had a similar problem, but the context was different (this was due to proxy settings and I didn't use Heroku) so I don't know whether the solution I used is an option for you (I post it here because my reply is too long for a comment).

I simply included these lines:

  autoInvalidate <- reactiveTimer(10000)
  observe({
    autoInvalidate()
    cat(".")
  })

In this way a dot is printed in the console by every passage of 10 secs and my app didn't gray out anymore (though this is not really a "user activity").