diff --git a/NEWS.md b/NEWS.md
index 51c7b8dc74..0d1a395378 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -10,6 +10,10 @@
 * `highlight()` now supports `on="plotly_selecting"`, enabling client-side linked brushing via mouse click+drag (no mouse-up event required, as with `on="plotly_selected"`). (#1280)
 * `raster2uri()` supports nativeRaster objects. This enables nativeRaster support for
   the `annotation_raster()` geom (#2174, @zeehio).
+* `plotlyOutput()`'s gains a `fill` argument which , allowing it have more flexible default sizing behavior, which will be useful in combination with `{bslib}`'s new `card()`. (#2192)  
+
+* `plotlyOutput()` gains a new `fill` parameter. When `TRUE` (the default), the widget's container element is allowed to grow/shrink to fit it's parent container so long as that parent is opinionated about its height and has been marked with `htmltools::bindFillRole(x, container = TRUE)`. (#2198)
+  * The primary motivation for this is to allow plots to grow/shrink by default [inside `bslib::card_body_fill()`](https://rstudio.github.io/bslib/articles/cards.html#responsive-sizing)
 
 ## Bug fixes
 
@@ -22,7 +26,6 @@
 
 ## Improvements
 
-* `plotlyOutput()`'s `height` and `width` now defaults to `NULL`, allowing it have more flexible default sizing behavior, which will be useful in combination with `{bslib}`'s new `card()`. (#2192)  
 * `ggplotly()` does not issue warnings with `options(warnPartialMatchArgs = TRUE)` any longer. (#2046, thanks @bersbersbers)
 * `ggplotly()` does not issue warnings related to use of deprecated `tidyr::gather_()` in internals. (#2125, thanks @simonpcouch)
 
diff --git a/R/shiny.R b/R/shiny.R
index d5b8f2e78d..583b4492f8 100644
--- a/R/shiny.R
+++ b/R/shiny.R
@@ -17,14 +17,15 @@
 #' @param env The environment in which to evaluate `expr`.
 #' @param quoted Is `expr` a quoted expression (with `quote()`)? This 
 #'   is useful if you want to save an expression in a variable.
-#'   
+#' @param fill see [htmlwidgets::shinyWidgetOutput()] for explanation (requires
+#'   a recent version of htmlwidgets).
 #' @importFrom htmlwidgets shinyWidgetOutput
 #' @importFrom htmlwidgets shinyRenderWidget
 #' @name plotly-shiny
 #'
 #' @export
-plotlyOutput <- function(outputId, width = NULL, height = NULL, 
-                         inline = FALSE, reportTheme = TRUE) {
+plotlyOutput <- function(outputId, width = "100%", height = "400px", 
+                         inline = FALSE, reportTheme = TRUE, fill = !inline) {
   args <- list(
     outputId = outputId, 
     name = "plotly", 
@@ -37,6 +38,9 @@ plotlyOutput <- function(outputId, width = NULL, height = NULL,
   if (is_installed("shiny", "1.4.0.9003") && is_installed("htmlwidgets", "1.5.2.9000")) {
     args$reportTheme <- reportTheme
   }
+  if (is_installed("htmlwidgets", "1.5.4.9001")) {
+    args$fill <- fill
+  }
   do.call(htmlwidgets::shinyWidgetOutput, args)
 }
 
diff --git a/inst/htmlwidgets/lib/plotlyjs/plotly-htmlwidgets.css b/inst/htmlwidgets/lib/plotlyjs/plotly-htmlwidgets.css
index 6e2ced6428..f35906d52c 100644
--- a/inst/htmlwidgets/lib/plotlyjs/plotly-htmlwidgets.css
+++ b/inst/htmlwidgets/lib/plotlyjs/plotly-htmlwidgets.css
@@ -1,8 +1,3 @@
-.plotly.html-widget {
-  width: 100%;
-  height: 400px;
-}
-
 /*
 just here so that plotly works
 correctly with ioslides.
diff --git a/man/plotly-shiny.Rd b/man/plotly-shiny.Rd
index 8d5ee7375d..bd7dd11e5f 100644
--- a/man/plotly-shiny.Rd
+++ b/man/plotly-shiny.Rd
@@ -8,8 +8,8 @@
 \usage{
 plotlyOutput(
   outputId,
-  width = NULL,
-  height = NULL,
+  width = "100\%",
+  height = "400px",
   inline = FALSE,
   reportTheme = TRUE
 )
@@ -37,6 +37,9 @@ version of shiny and htmlwidgets is available).}
 
 \item{quoted}{Is \code{expr} a quoted expression (with \code{quote()})? This
 is useful if you want to save an expression in a variable.}
+
+\item{fill}{see \code{\link[htmlwidgets:htmlwidgets-shiny]{htmlwidgets::shinyWidgetOutput()}} for explanation (requires
+a recent version of htmlwidgets).}
 }
 \description{
 Output and render functions for using plotly within Shiny