It sometimes happens that - when I slide the right-hand side of a project back to the left with the Spacer Tool, to rejoin the left-hand side I was working on - the Spacer Tool refuses to close the last frame. So there's a gap of 1 frame. I each time checked if there was no content on other tracks that was blocking the slide, but that was never the case.

I can drag the lead part of the right-hand side against the lead part of the left-hand side, where it is supposed to snap too, but as soon as I release the mouse, it snaps back to a 1-frame gap. Sometimes, after doing this a number of times, the problem is suddenly solved. But other times, it's not.

Is this a bug?