Oh right, it seems the comment-field bug happens when you use the letter-spacing tag that adjusts character spacing.
Literal
Ah yeah-yeah, comment-column [of-の] bug [topic-は] character-spacing [object-を] adjust letter-spacing tag [object-を] use [when-と] happens thing was [seems-みたい].
Tech-blog register, casual self-diagnosis of a website bug. 文字間 'character spacing' gets a translation to English inline (letter-spacing), and タグ refers to the HTML/CSS tag. The ~と here is the natural-consequence conditional 'when X, then Y always follows.' ものだった (ものだ past form) marks this as a realized truth about how things were — 'so that's what it turned out to be.' みたい softens it to 'it seems.'