Change in text rendering between versions?

[Spoon]

I wanted to edit some older files using the original Pixelmator since the new Pixelmator didn't open them properly and noticed the way text is rendered has changed at some point. Text now seems noticeably bolder. The change must have happened between July and now.

I've included two images as an example, the first is a screenshot of the preview image from when the file hadn't been opened in a later version, the second from after. The font in question is Plantin, though other fonts seem bolder as well.




Is there a way to revert back to the original way of rendering or change how text is rendered in general?