Some mates in an assembly get suppressed in an assembly even if those parts are not involved in configurations.
I assume you mean new mates are automatically suppressed in inactive configurations? If yes, de-select this option in the configuration properties.
Thanks Glenn for replying to my query. However, there's not a single thing that comes out when I click on the Property icon.
You apparently clicked on the Properties tab first, which is understandable since that's what my screenshot shows. First you need to click on the Configurations tab instead, then right-click on the configuration name and choose "Properties" from the drop-down.
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