Elementary Tweaks doesn't list personal Plank themes

Using Elementary Tweaks on Freya from https://launchpad.net/~bmeznarsic/+archive/ubuntu/tweaks-freya

It seems that Tweaks doesn't see Plank themes that are in the user folder (~/.local/share/plank/themes). If I put one there, it doesn't appear in the list. If I edit Plank's config file manually, it works fine, the theme is applied (so it's not a problem with the theme itself). Then in Tweaks, the widget displays nothing as a selected theme until I switch to another one listed.