It seems Facebook completely dropped my support (but not for other people I know) for searching for messages. I can only look for conversation names (persons, pages or chat group names) or search for messages inside a specific chat.
This directly contradicts what Facebook's official support states, and as mentioned it does work for other people. It doesn't work for me in any browser.
Any idea what causes this and how to fix it?
This is how it looks like now:
If I choose a specific chat, I can search by clicking "Customize Chat" first, although what does search have anything to do with customization? It's as if they don't want people to know search is possible within a specific chat:
This is how other people can search for all past messages:
And this is how they (used to?) search inside specific conversations: