Split from T239083. As I wrote there, I could reproduce the issue on https://it.wikipedia.org/wiki/Che_Guevara three times, so it seems to be pretty consistent.
What I did is:

• Deleted the page
• Went to Special:Undelete, and:
  • Selected the first 30 revisions
  • Hit "Invert selection"
  • Add to the selection two revisions amongst the 30s
  • Hit "Restore"
• The page was successfully restored (although I faced T239106)

Observed: If you head to that page's history (link), you can see that the edit by 5.90.14.47 on Nov 18 has a size delta of "+111909". That's obviously wrong if you look at the diff, or even just at the size of the previous revision (it should be +1).

The number shown is the size of the whole page, and this is certainly not a coincidence.