In the Parshah of Chayei Sara, in Bereishis 25:6, there is a Posuk that refers to הפילגשים - "the concubines". Rashi expounds that since the word is missing a Yud, it must be a reference to the fact that Hagar and Keturah were one person and that is how the Torah is alluding to this fact (see Rashi there).
The question is: What missing Yud?
Artscroll's comment answers that: "Rashi's text of the Torah had the spelling פילגשם, without the letter י of the ים suffix which indicates the plural ..."
Does this mean that in Rashi's time the text of the Torah was actually slightly different - so much so that Rashi took the effort to expound a particular missing Yud that we don't actually have on our modern Torah scrolls?
If so, wouldn't it be more appropriate for modern Sofrim to "fix" this issue by leaving out the Yud (since we can trust Rashi on this presumably)?
I'm curious about this.