Indesign 17 on MacOs 12.3.1

Convert Footnotes and Endnotes does not work when the footnotes does not have a footnote number.

I have an Indesign document with footnotes.
In each footnote I have removed the footnote number and the following tab character. (~F\t)

I need these footnotes to be endnotes but this is not possible with the command "Convert Footnotes and Endnotes".

Without the footnote number in the footnotes the command/script does not recognise the footnotes as being footnotes.

They are however still footnotes and I can continue working with them as footnotes and also address them via scripting but the command "Convert Footnotes and Endnotes" does not work.

I can reinsert a footnote number in each of the footnotes manually one by one by going through "Special Characters > Markers > Footnote Number.

This will make the conversion work but this should not be necessary.

Now to the bonus problem:

I figured I could simply iterate the footnotes and insert the footnote number with a simple script. Guess what? Not that simple.

I can insert everything except for the SpecialCharacters.FOOTNOTE_SYMBOL in the footnotes.
Looking at the undo menu it appears as if indesign thinks it has inserted something as it says: "Undo Insert Text"
But nothing was inserted.

So ... I guess that I have two bugs here.

Please help.