Zoom in for "Run in Window" or "Preview in Window"?

Zooming works fine in Rstudio and when previewing a knitted document or a shiny app in the Viewer. However, when using "Run in Window" for a shiny app or "Preview in Window" for an Rmd file, there doesn't seem to be an option to increase the size of the window content (at least on Mac).

Using CMD-= will increase the zoom level in Rstudio but does not (dynamically) update the zoom level in the Window. Closing the window, increasing the zoom level in Rstudio, and then opening the window again does work however.

Is there a option to make the zoom level in the "Preview" window update dynamically?