I just upgraded some software on the site, and apparently the lower-case letter “i” is disappearing from comments. I swear this is not a practical joke, and if you are currently having this problem, please comment below. Apparently, the capital letter “I” is still safe to use.
Update: This is now fixed for sure. Someone else reported this problem and identified how to patch it. I assume the offending software will be updated again shortly to correct the issue permanently.