the.com/filter bubble

means A personalized information environment, shaped by algorithms and your own past clicks, that mostly shows you things you already agree with and quietly edits out the rest.

from A 21st-century coinage, popularized by internet activist Eli Pariser in his 2011 book of the same name. 'Filter' points to the sorting algorithms that curate your feed behind the scenes; 'bubble' borrows the old sense of an enclosed, fragile sphere separating you from outside air — here, from outside opinions. Pariser was describing how search engines and social platforms, trying to predict what you'd like, ended up narrowing what you'd ever see.