Resolved - R Shiny - Navigation containers expect a collection of

An error has occurred!

Navigation containers expect a collection of `bslib::nav_panel()`/`shiny::tabPanel()`s and/or `bslib::nav_menu()`/`shiny::navbarMenu()`s. Consider using `header` or `footer` if you wish to place content above (or below) every panel's contents.

Solution:

My current shiny version was 1.7.X, which gave me the above error. 

Downgrading shiny version to 1.6 solves the problem. I delete the shiny version 1.7.X version from the packages and installed 1.6 in R console using the below command:

remotes::install_version("shiny", "1.6.0")

When you deploy your Shiny app to a server or cloud service (e.g., shinyapps.io), the server environment typically uses the version of Shiny that's installed in that environment.

You don't explicitly specify the Shiny version when deploying; instead, the server environment determines which version of Shiny to use based on its package setup.