R Shiny Leaflet issue

I am referencing to the issue mentioned by @esbriskin. I have also made a Shiny map using leaflet but I am having trouble while I browse through different tabs and come back to World map, the map doesnt pop-up.

Also, it should have some output once it is selected. I have to change the year in order to see the output.

Can you please help me with this.

Best,
Manan