Issue in the second example of section 6.5.2. Shiny themes

[ArthurDentDK]

In this example:

theme <- bslib::bs_theme(
  bg = "#0b3d91", 
  fg = "white", 
  base_font = "Source Sans Pro"
)

Using <- instead of = gives an erroneous output in the app (lots of text at the top). (Tested with R version 4.2.3, shiny_1.7.4, and bslib_0.4.2).
The example is correct if "theme" is interpreted as a variable defined in the example and inserted like this:

ui <- fluidPage(
  theme = theme,
  titlePanel("A themed plot"),
  plotOutput("plot"),
)

But it seems confusing to use the same name for the variable and the parameter, so I assume it is a mistake or a changed behavior after package updates.