>>There is an option to unsubcsribe from one category in the particular forum if you go to your account Advanced settings. I know I've done it before for Chatter forum.
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>I want to subscribe to Chatter, so it's checked. But I don't find any Religion checkbox.
See two attached screenshots. You will need to press Add button to add that category to your filter.
If it's not broken, fix it until it is.
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