Issue description
Your project contains a large number of essential objects, and your 3D view is starting to lag.
Solution
To improve performance, use the Model View Options to adjust the detail level for objects and lamps under Miscellaneous Settings.
Object and Lamp Detail Level
Set the 3D projection detail level to reduce complexity so you can work in a faster view.
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By default, objects and lamps use the detail level set in the model view options. If needed, you can override the detail level for specific objects or lamps in their Element Settings, using the 2D or 3D representation controls, if this option is available.