When I open some of my assemblies my compnents automatically switch to lightweight/blue feather icon. Why is this and can I stop it from happening in the future. It's a real annoyance clicking the 'set to resolve'.
Uncheck the option shown in the pic and you should be good to go.
You can improve performance of large assemblies significantly by using Lightweight components. Loading an assembly with lightweight components is faster than loading the same assembly with fully resolved components. Assemblies with lightweight components rebuild faster because less data is evaluated.
Lightweight components are efficient because the full model data for the components is loaded only as it is needed. Only components that are affected by changes that you make in the current editing session become fully resolved.
Apart from setting up the option, to set one or more lightweight components to resolved:
For a single component, right-click the component and select Set to resolved.
For an entire assembly, right-click the top level assembly icon and select Set lightweight to resolved.
For a sub-assembly and its components, right-click the sub-assembly icon and select Set lightweight to resolved.
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