I found a Twitter account that appears to be completely shadowbanned from any type of search yet their tweets do show as replies to other people's tweets. That's really interesting.
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"Search Suggestion Ban
This type of ban causes an account to not populate search suggestions and people search results when it is searched for while being logged out. Twitter seems to take tie strength or a similar metric into account. While an account may be suggested to users..
you are strongly tied to, it may not be shown to others."
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"Search Ban
This type of ban causes your tweets to be hidden from the search results entirely, no matter whether the quality filter is turned on or off. This behavior includes hashtags as well. This type of ban seems to be temporally limited for active accounts."
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