Why when I opened old file in Layout it got heavy after update?

is anyone know how to fix this heavy old file ?
I’m using 2023 Layout before then I update to 23.3 something (forgot)
I’m trying to open my old file to do some revision but it turns out so heavy even just to move

It is probably bloated, or corrupted. Post the .Layout file so it can be examined.

Are the model views using Vector or Hybrid rendering? If the model has somewhere near a million entities (edges and faces) it will be slow with Raster or Hybrid, or almost impossible to export with Output Override (Document setup>Rendering) turned on.