[LyX/master] Add conversion routine for format 612.

[Jean-Marc Lasgouttes]

Le 07/12/2022 à 17:19, Richard Kimberly Heck a écrit :
>> I see a lot of
>>   lyx2lyx warning: noprefix "false"
>> in the console when loading files. Is this a forgotten debug message ?
> 
> I was assuming that should be there, but perhaps it's not a problem if 
> it isn't?
> 
> Maybe we don't even need this conversion. The files load fine without 
> it, though it caused problems with the lyx2lyx tests, apparently, not to 
> have it. (The new param *is* added on save.)

My problem is not with the conversion, but with the warning. It does not 
seem to do anything useful.

JMarc