FS, please stop deleting women's surnames in indexes
When a woman's surname is indexed as being the same as her husband's, FamilySearch runs an automated process on the text entered by indexers and removes that field from the published index.
In the part of the world where my ancestors lived, this process removes valid data from the index basically 100% of the time: the practice of taking one's husband's family name as one's own simply didn't exist in Hungarian-speaking communities, and even in the German-speaking ones where it did, it was not generally used in registers and other official contexts. Therefore, when an indexer entered "Günther" as the mother's surname on Friederica's baptism (https://www.familysearch.org/ark:/61903/1:1:KDF2-CFB), this was not an error: that was her maiden name, as well as her husband's surname. It should not have been removed from the index. The removal makes it look like the mother's surname was not recorded, but it was, very clearly: Frau Rosine Günther geb. Günther "Mrs. Rosine Günther born Günther".
The index entry in question was published recently (like in the last few months), so this automated process is still active and in use. Please retire it. It disimproves your data and throws away the hard work of your indexers.