Waiter with a custom spinner

custom_spinner.R

library(shiny)
library(waiter)

spinner <- HTML(
  '<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" width="100px" height="100px" viewBox="0 0 100 100" enable-background="new 0 0 100 100" xml:space="preserve">
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	C87.939,71,71,87.9,50,87.936z"/>
<path fill="#013d75" stroke="none" class="rim" d="M50.005,16.177c-18.677,0-33.823,15.146-33.823,33.823s15.146,33.8,33.8,33.823C68.654,83.823,83.8,68.677,83.8,50
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	c1.709,1.2,5.6,4.5,6.7,6.533c1.128,2,1.399,3,0.8,3.643c-1.094,1.182-10.889,4.204-12.046,4.3
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</svg>'
)

ui <- fluidPage(
  use_waiter(),
  tags$style(
    ".tire {
animation: rotation 1800ms infinite linear;
transform-origin: 50% 50%;
}
.rim {
animation: rotation 1200ms infinite linear;
transform-origin: 50% 50%;
}

@keyframes rotation {
from {transform: rotate(0deg);}
to   {transform: rotate(360deg);}
}"
  ),
  waiter_show_on_load(spinner, color = "white")
)

server <- function(input, output){

}

shinyApp(ui, server)

Very useful thank you so much.