Tzitzis In or Out

Is the minhag of Franfurt to tuck in the tzitzis or to show them?

I don't know whether this applies to all of Frankfurt, but my grandfather ז”ל was quite opposed to the practice of leaving one's tzitzis out. Furthermore, his brothers in law did/do not wear theirs out.

In Frankfurt, this would likely have been seen as a breach of decorum, particularly considering R' Neuberger's memoir in this website.

Also, most pre-war gedaulim were known for tucking their tzitzis in, including the Chofetz Chaim of Radun, despite his p'sak in the Mishnah Berurah.

I asked this question to R. Hamburger in regards to today, and he told me it was best to wear them out if you can.