Click the hamburger icon in the upper left (talking as if you are in mobile web) Go to communities. The page always lists your local communities first, click all.

In the search box put the full address. It looks like, !name@domain.tld. For example, !cats@lemmy.world

Hit search and wait patiently for up to 15 seconds. Important.

You will see the community show up (unless it’s blocked) and you click the link it shows you.

Click on the + for their Sidebar. Click Subscribe

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