I often code functions in the following way by creating a basic function, entering debug mode, and then writing the function in debugmode. E.g.,
myfun <- function(x) print(x)
debugonce(myfun)
myfun("test")
The benefits of this is that I can get real time feedback on whether my code is working with the arguments passed to it.
However RStudio appears to have recently changed it's behaviour to make this more difficult. I recently upgraded to 2021.09.0 Build 351.
Previously, it would open the Source Editor when you call this command.

But if you closed this screen, you could return to your code, edit the code, evaluate code, and so on without the viewer re-appering.
However, now it seems to reappear every time you evaluate your code.
For instance, if I close the viewer, go back to my main script, and evaluate x, the Viewer opens back up.
This is super annoying for someone used to editing and evaluating code while in debugmode using the source script file.
Is there any way of entirely disabling the Source Editor view in Rstudio? Or alternatively, is there a way of being able to edit and evaluate code without the Source Editor constantly re-appearing in Rstudio (like how it used to work)?
My current fix is to downgrade to Version 1.3.1093, where you could edit and evaluate code without the Viewer constantly re-appearing. But it would be a shame to miss out on future upgrades.