Feed list entry becomes indented after changing properties

[Qrox]

After changing the properties of an entry in the feed list (the leftmost column), the entry becomes indented without a clear meaning. Changing the properties back does not fix the problem.

It seems the HTML element of the entry has data-in-folder="undefined", and the CSS includes a rule for [data-in-folder] to pad the element on the left for 30px, 15px more than the normal padding.

To me it seems like the data-in-folder attribute of the entry is miscalculated, and the [data-in-folder] rule is supposed to indent the entry in some other situation but is errorneously applied to the entry with the "undefined" attribute value.

Edit: I'm using Chrome.