I don't think it's actually permanent though, is it? The items will eventually come back.
It's permanent. However, behind the scenes I'm sure it's using CSS selectors to identify the element you're blocking, and if the server changes that, then it wouldn't detect that exact element anymore.
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It's permanent. However, behind the scenes I'm sure it's using CSS selectors to identify the element you're blocking, and if the server changes that, then it wouldn't detect that exact element anymore.