Sometimes the usage of hiragana or katakana in reading fields in the JMdict database is not in alignment with the corresponding expression fields.
For example, the expression タチの悪い has a corresponding reading equal to たちのわるい in JMdict.
When headwords like this are displayed in Yomitan, the タチ part of the word receives たち furigana.
I suppose this is nice if you can't read katakana, but I'm not sure if that's a big concern. I think it might look better if タチ did not display any furigana here.
Sometimes the usage of hiragana or katakana in reading fields in the JMdict database is not in alignment with the corresponding expression fields.
For example, the expression タチの悪い has a corresponding reading equal to たちのわるい in JMdict.
When headwords like this are displayed in Yomitan, the タチ part of the word receives たち furigana.
I suppose this is nice if you can't read katakana, but I'm not sure if that's a big concern. I think it might look better if タチ did not display any furigana here.