Normally I have no trouble with this. In FCP X 10.4, I just select the cross-dissolve, hover over it, and I can drag left or right. I have one however that won't let me, as if the cross dissolve is too thin, I can grab it but it edits the entire clip (and seems to move around the entire project) instead of just letting me lengthen the cross dissolve. I need to fade in and fade out of this clip. Help! Thank you for any replies.