Issue in converting Pluto notebook to Jupyter notebook

[VarLad]

The produced notebook apparently reports invalid JSON.
I'm trying to find a good MWE. For now I suspect two things in a notebook. A cell with:

struct Xyz
    s::String
end

or

macro qmd_str(s)
  quote
    Xyz(s)
  end
end

qmd"""
Something
"""

[emmaccode]

(@v1.11) pkg> activate .
  Activating project at `~/dev/packages/parametric/IPyCells.jl`

julia> using IPyCells
Precompiling IPyCells...
  1 dependency successfully precompiled in 1 seconds. 10 already precompiled.

julia> cell1 = IPyCells.Cell{:code}("struct Xyz
           s::String
       end")
IPyCells.Cell{:code}("pgdgv", "struct Xyz\n    s::String\nend", "")

julia> cell2 = IPyCells.Cell{:code}("""macro qmd_str(s)
         quote
           Xyz(s)
         end
       end

       qmd""\"
       Something
       ""\" """)
IPyCells.Cell{:code}("nrftn", "macro qmd_str(s)\n  quote\n    Xyz(s)\n  end\nend\n\nqmd\"\"\"\nSomething\n\"\"\" ", "")

julia> IPyCells.save_ipynb([cell1, cell2], "samp.ipynb")

julia> 

• (notebook opens with VSCode,) so I figure it is the output.

This .ipynb reader seems to assume we are coming from Julia, and particularly with a String as outputs... It certainly needs changes to facilitate Pluto better. I went ahead and made them on Unstable, it sounds like there is a good chance a breaking character for a String or bad escape character was accidentally added from the output of the cells.

Unfortunately, I was not able to replicate the issue, but I am familiar with this causing this issue in nbformat. For now, I will add an explicit type conversion (on Unstable) it would be nice if that worked... If not, in the future, there might be a specific character discrepancy between JSON/Julia strings that is missing from the replacement, which will require replicating this. Thanks for the issue, I appreciate you for making this package better.