Upgrade notes for Shiny 1.9.0

New busy indication feature

Add the new useBusyIndicators() function to any UI definition to:

  1. Add a spinner overlay on calculating/recalculating outputs.
  2. Show a page-level pulsing banner when Shiny is busy calculating something (e.g., a download, side-effect, etc), but no calculating/recalculating outputs are visible.

In a future version of Shiny, busy indication will be enabled by default, so we encourage you to try it out now, provide feedback, and report any issues.

In addition, various properties of the spinners and pulse can be customized with busyIndicatorOptions(). For more details, see ?busyIndicatorOptions. (#4040, #4104)

New features and improvements

  • The client-side TypeScript code for Shiny has been refactored so that the Shiny object is now an instance of class ShinyClass. (#4063)

  • In TypeScript, the Shiny object has a new property initializedPromise, which is a Promise-like object that can be awaited or chained with .then(). This Promise-like object corresponds to the shiny:sessioninitialized JavaScript event, but is easier to use because it can be used both before and after the events have occurred. (#4063)

  • Output bindings now include the .recalculating CSS class when they are first bound, up until the first render. This makes it possible/easier to show progress indication when the output is calculating for the first time. (#4039)

  • A new shiny.client_devmode option controls client-side devmode features, in particular the client-side error console introduced in shiny 1.8.1, independently of the R-side features of shiny::devmode(). This usage is primarily intended for automatic use in Shinylive. (#4073)

  • Added function reactlogAddMark() to programmatically add _mark_ed locations in the reactlog log without the requirement of keyboard bindings during an idle reactive moment. (#4103)

Bug fixes

  • downloadButton() and downloadLink() are now disabled up until they are fully initialized. This prevents the user from clicking the button/link before the download is ready. (#4041)

  • Output bindings that are removed, invalidated, then inserted again (while invalidated) now correctly include the .recalculating CSS class. (#4039)

  • Fixed a recent issue with uiOutput() and conditionalPanel() not properly lower opacity when recalculation (in a Bootstrap 5 context). (#4027)

  • Image outputs that were scaled by CSS had certain regions that were unresponsive to hover/click/brush handlers. (#3234)