disable 3d scene to improve performance of compositor, VSE, and image editors..

Performance of Blender's non 3d related modes, such as the compositor, VSE, and image editors, are impacted by the 3d scene's expensive calculations, such as modifiers, particle systems, physics, complex rigs, etc. These generally don't need to be calculated when not working with the 3d viewport.

For a big performance increase when working on those sort of tasks, a 'disable 3d scene calculation' button could be added, or perhaps an easier implementation would be to give the 'Scene Collection' an 'exclude from viewlayer' checkbox just like it's child collections.

Another solution would be an option in the user preferences to only calculate the 3d scene when a 3d viewport is visible and or when rendering. Although it would still be nice to be able to disable the 3d scene from calculating when the 3d viewport is visible, just so you can quickly temporarily stop calculation without changing workspaces.