Excel online - Duplicate tabs has been replaced with Copy and Paste

Hello,

This morning as I came into work, I saw a note saying my work associate cannot duplicate a tab on excel online, so I've had a bit of a play with it this morning, but stretched my limit of trouble shooting, which is why I'm here as a last resort.

I use microsoft edge on 1 PC and Chrome on another and both PC's are doing the same thing, it doesn't matter if it's a new excel work book or what ever it does the same thing.

This is how it looks currently:

This is how it looks on another browser:

On the PC that uses chrome I checked with edge, and the option to duplicate a tab is there, so I don't know what's going on, did microsoft update and remove the duplicate feature from excel online?

I have tried:
- Searching the internet

- Resetting my chrome settings and history

Usually I am fine with excel online but this option has me baffled as I know it's not a faulty file, it can't be someone's used the office 365 application to enable/disable options because it works in a "fresh" browser.

My only guess is microsoft's done an update that doesn't reflect on the "fresh" browser, and if so then that's really poor as my work colleagues NEED that duplicate option as their excel knowledge is very limited.

Thanks for your time on this really silly issue that shouldn't even be an issue, but microsoft be microsoft I guess.


EDIT: I have tried to log-in with a different account and it appears that account the duplicate is back.

I actually have no idea what is going on here, that just confuses me more, what are you doing microsoft?

Edit 2: I can confirm it's account based, new excel files that I make don't have the duplicate feature, I logged into the edge browser and sure enough the duplicate feature doesn't exist, instead it's "copy" and "paste".