I have two clips of the same scene that need to be played in parallel, side by side. They were filmed simultaneously from different viewpoints. When I try to overlay one clip onto the other, the first clip gets split into two and the second clip inserted into the gap, there's no pop-up menu offering the side-by-side merge.
And I suspect that the need to be resized first so it's genuinely side-by-side, not half-of-one-next-to-half-of-the-other. I haven't yet found the resizing function...
I do have advanced tools showing (according to the application prefs).
On a related issue, how do you turn off the 'helpful' editing tips? It's getting really irksome to have it suggest that my video might be improved by selecting little bits of each clip. In this case it's for archival research use so I need to keep everything. I have a stack of these to work through so turning off those 'helpful' tips would be very helpful indeed.
I just happened to think of a workaround you might try.
Rather than side by side, what if you used picture in picture and place your first video over black and then export it.
Now re-import what you just exported and place your 2nd movie by doing another picture in picture effect.