Sidebar open/close transition not smooth on RHEL

On the latest and dev version of {bslib}, the sidebar is jerky when opening and closing.

I tried this on two systems, one RHEL 8 and another on Windows 10, using similar R versions (4.4.1) and package versions. The one on Linux is jerky, the attempt on Windows 10 performed as normal.

It is easier to show than explain... this is the experience on the Linux machine using the example from the bslib website:

library(shiny)
library(bslib)

ui <- page_sidebar(
  title = "My dashboard",
  sidebar = "Sidebar",
  "Main content area"
)

shinyApp(ui, function(input, output) {})

https://github.com/user-attachments/assets/af95a8cd-95d4-4118-b47e-e5c52f9138fe

Session Info: Linux

R version 4.4.1 (2024-06-14)
Platform: x86_64-pc-linux-gnu
Running under: Red Hat Enterprise Linux 8.9 (Ootpa)

Matrix products: default
BLAS/LAPACK: /usr/lib64/libopenblasp-r0.3.15.so; LAPACK version 3.9.0

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] bslib_0.8.0.9000 shiny_1.9.1

loaded via a namespace (and not attached):
[1] vctrs_0.6.5 cli_3.6.3 rlang_1.1.4 promises_1.3.0 jsonlite_1.8.8
[6] xtable_1.8-4 glue_1.7.0 htmltools_0.5.8.1 httpuv_1.6.15 sass_0.4.9
[11] rsconnect_1.3.1 fansi_1.0.6 jquerylib_0.1.4 tibble_3.2.1 fastmap_1.2.0
[16] lifecycle_1.0.4 memoise_2.0.1 compiler_4.4.1 bsicons_0.1.2 fs_1.6.4
[21] pkgconfig_2.0.3 Rcpp_1.0.13 rstudioapi_0.16.0 later_1.3.2 digest_0.6.37
[26] R6_2.5.1 utf8_1.2.4 pillar_1.9.0 magrittr_2.0.3 tools_4.4.1
[31] mime_0.12 cachem_1.1.0

Use the provided page_sidebar() Shiny example as the reproduction entry point, comparing the sidebar transition on RHEL 8 and Windows 10 with the stated R, bslib, and Shiny versions. Done means the sidebar opens and closes smoothly on the reported Linux setup without regressing the normal Windows behavior; the payload names no source file or test.