Create a fixed Viewer pane instead of spawning new ones

[vitallish]

Is your feature request related to a problem? Please describe. I'd like to be able to wrangle the amount of 'Viewer' tabs that are created. I make a lot of tables with flextable and each time I make one a new Viewer pane is spawned.

Describe the solution you'd like Ideally, I would be able to have one Viewer pane that gets updated - similar to how the R Plot pane works. If that's not possible, then it'd be good to be able to define which group new Viewers get opened in.

Describe alternatives you've considered I'm not aware of any other alternatives to this - I've looked around the settings and I can't seem to find anything that controls this.

Additional context None - I'm happy to work on this as well, if you could point me in the right direction.