How to compare and manage .po files

Hello Community and Support,

what kind of software do you use to handle with .po files and to manage them, e.g for all your translation projects? Do you work with gettext?

I do use poedit, but I can not find how to compare 2 .po files to make a difference of the strings and find out which strings are contained in another .po file in which not.

There are also the online tools like poeditor.com and transifex. Did you mentioned in some forumpost, why you moved back from transifex? I never had opportunities to do translations, so I would like to find out best practices :).

Thank you, Marius