Go to your “settings” (the little gear-shaped icon),
click “account” on the left-hand side
near the bottom should be a rounded rectangle that says “ignored users”
click the “ignored users” box and it brings up a dialog line that says:
"Enter the URL or username of a tumblelog to ignore"
enter the ones you want to ignore, one at a time.
[ those are the only ones that have hit me so far. ]
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