TT #739 · Parashas Ki Seitzei · Seventh Aliyah · Passuk 25:09
Then his yevamah shall approach him in the presence of the elders, and draw his shoe off his foot, and spit in his face, and respond and say: “Thus shall be done to the man who will not build up his brother’s house.”
Torah Temimah points to Yevamot 103a.
TT lemma: וְיָרְקָה בְּפָנָיו.
הַסּוּמָא אֵינוֹ חוֹלֵץ, שֶׁנֶּאֱמַר וְיָרְקָה בְּפָנָיו – וְאֵין זֶה רוֹאֶה אֶת הָרוֹק.
English: A blind man does not perform chalitzah, for it is said “and she shall spit in his face” — and this one does not see the spittle.
On the daf / in context: Some authorities treat the inability of the yavam to see the spittle as a disqualification (at least le-khatehillah).
Derash regarding a blind yavam.
A blind yavam is preferably not the one who performs chalitzah (or, according to some, his chalitzah is invalid).