Resizing issue with insert command in a cue

I was just playing inserting some commands in a cue, a insert the command open snapshot1 in the first cue and open snapshot2 in the second cue, when i start the cue my esternal window1 make a series of strange resizing try and then change the snapshot, idem for the second cue, i upload a video of this happening, in the reality it is more annoying then in the low res video. My screen res is always 1366 for both main and external monitor, didnt try working at (2.4 MB)