[BUG] - error when deleting axis with duplicate curves

[shilorigins]

Describe the bug

I have an axis with the same PV plotted twice. When I try to close the axis, I get this error:

Traceback (most recent call last):
  File "/sdf/home/d/devagr/src/trace/trace/widgets/control_panel.py", line 217, in close
    self.layout().itemAt(i).widget().close()
AttributeError: 'NoneType' object has no attribute 'widget'

One of the curves is deleted, but the other curve and the axis persist. Trying to delete the axis again works as expected.

Expected behavior

Deleting an axis should complete successfully regardless of how many / which curves it contains.

Steps to Reproduce

That's in Describe the bug

Possible solution (optional)

No response

My platform

No response

Additional context

No response

[shilorigins]

The bug actually occurs regardless of what the curves' addresses are. The cause is that curves are removed while iterating over the list's indices, so half of the indices become invalid.