Very long time rendering in new 1.3.1 version

I got new 1.3.1 version of Synfig recently. I wondering why the same project (about 1 minute long with simple animation) takes about twice more time to render comparing to older 1.2 version?

Probably related to … -276744427 . I suppose optimizations works differently for various kinds of scenes, so it might affect your case negatively.