Does contentbird check for a duplicate when saving a new source?

A duplicate source is only detected, if the URL, the linktext, the linktarget and the project exactly match. For example, if a source is stored only with the desired linkorigin and nothing else it will be detected as a duplicate, when trying to save it that way again. No linktext, no linktarget and no assigned project are also regarded as exact match, if one of the fields is filled in it will not be detected as duplicate.