Confusing error message when attempting to use a translated column that doesn't exist

[lognaturel]

Forum post: https://forum.getodk.org/t/error-when-compiling-xlsform-dict-object-has-no-attribute-nodetype/57638

This feels like it should be an error. It could be something generic like "On the sheet, the column name is invalid." or include details about that column on that sheet not being translatable.

[tiritea]

FWIW, this is the same error you get - “Error: ‘dict’ object has no attribute ‘nodeType’” - if you inadvertently try to add a translated form title (!), which folks seem to attempt not infrequently...

or include details about that column on that sheet not being translatable.

If its readily identifiable that it is due to a translation gone awry, then certainly something like "Error: trying to add translations to a non-translatable column 'form_title' on sheet 'settings'" would be great.

[lognaturel]

if you inadvertently try to add a translated form title (!), which folks seem to attempt not infrequently

Yes, that is a very logical extension of the translation model and I think we should consider a targeted message for that case specifically since it's weird that it's not supported. The only reason that it's not is because it's on top of the title spec for HTML.