Main form with button A to open Form A and then disable button A until Form A is closed. Do the same with B

In my Visual Studio project file: <TargetFramework>net6.0-windows</TargetFramework>

I have a Winforms application whose main form has two buttons, button A and button B.

I have coded button A so that it disables itself when clicked, launches form A, and when form A is closed, control returns to the button click event where button A is re-enabled:

            btnA.Enabled = false;            
            FormA frmA = new FormA();
            btnA.Enabled = frmA.ShowDialog(this) == DialogResult.OK;

However this does not allow the user to do anything on the main form until frmA is closed.

When button A is clicked, I still want to disable button A so that the user cannot open another form A. But I also want the user to be able to click button B on the main form and have that logic work the same way: disable button B, launch form B, re-enable button B.

What I am trying to do is give the user the ability to launch one form A and one form B from the main form. Can I accomplish that with the pattern I've described? If so, how? (Note: There could be buttons C and D later.) I would gladly consider a different/better approach. Thanks Hedge.