Hi Little_Joes,
It seems there’s some disconnect from what I’m seeing when trying to reproduce this versus what you are seeing. When inserting a large model from the toolbox, the blue loading circle does not appear. What I do see is an “Inserting” green loading bar at the bottom of the window:
Could you send another Gif of the full Studio window starting from before you insert a big model from the toolbox? There may be something I can pick up on based on when the blue loading circle appears.
Also if you could send logs that could help track down what’s happening as well: How to post a Bug Report - #12 by Roblox
Thanks