Steps to reproduce:
 - open Hugin (it's not necessary to open/create a project)
 - File > Preferences... > Assistant > User-defined output options > Configure
 - 13 consecutive assertion failures ensue.

Relevant console output:

   (hugin:1777180): Gtk-CRITICAL **: 18:35:02.952: gtk_widget_set_size_request: assertion 'width >= -1' failed
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Canvas" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Condition1" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Condition2" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Crop" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "FOV" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Projection" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Canvas" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Condition1" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Condition2" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Condition3" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Crop" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "FOV" already exists
   ./src/propgrid/propgridpagestate.cpp(1672): assert ""Assert failure"" failed in PrepareToAddItem(): wxPropertyGrid item with name "Projection" already exists

When the dialog eventually appears, I note that the 13 asserts likely
correspond to the 13 rows in the table for the "Equirectangular" and
"Rectilinear" sections (which all have the same names as those in the
"Cylindrical" section).

Further, clicking on one of the rows causes another assertion failure:

   /usr/include/wx-3.2/wx/propgrid/manager.h(276): assert ""Assert failure"" failed in GetIterator(): Please only iterate through individual pages or use CreateVIterator()

This all smells like Hugin using WX wrongly. 2024.0.1+dfsg-1 has the same
problem; I upgraded to the version in testing in case it helped.