Allow batch mode (gROOT::SetBatch) to be changed from true to false in middle of session

[will-cern]

Feature description

Hello,
I have noticed that if I start a python session in batch mode (ROOT.gROOT.SetBatch(True)) and run some lines that would draw some things to a canvas, if I subsequently set ROOT.gROOT.SetBatch(False) in the same session, I am unable to visualize new canvases.
Is there a way to switch between batch mode in the same session? It would be great if this was supported!
Thanks
Will

Alternatives considered

No response

Additional context

No response

[ferdymercury]

It works fine directly in Cling:

gROOT->SetBatch(kTRUE);
new TCanvas();
gROOT->SetBatch(kFALSE);
new TCanvas();
gROOT->SetBatch(kTRUE);
new TCanvas();

But indeed fails in Python:

import ROOT
ROOT.gROOT.SetBatch(True)
c = ROOT.TCanvas()
ROOT.gROOT.SetBatch(False)
c2 = ROOT.TCanvas()
ROOT.gROOT.SetBatch(True)
c3 = ROOT.TCanvas()

[ferdymercury]

@will-cern Could you try applying this change? #18911
(Rebuilding is immediate).