What do the random lines under every option in the menus mean?

[Folliful]

I’m talking about the underline under a (seemingly) random letter of every single option under all of the menus. At first I thought they might indicate a shortcut key. “New File” underline’s the N, and control+N does open a new document, but this doesn’t follow many of the other options, and I tried all of the combinations of control, alt and shift (though maybe I just missed some?)

My second thought was it was just to make them all stand out, but why only underline a single letter? Not even the first letter. “Recent Documents” underlines the U, for example.

I’m just curious. I can’t think of any other reasons.

[Villeroy]

Mnemonic menu shortcuts exist as a feature of desktop applications since the early 90ies.
Hold the Alt key, F U 1 calls File>Recent_DocUments>1. latest_file

37 years before now: File View Special

[Folliful]

that is actually really cool. I hadn’t realised there’s a whole other system of short cuts, and it works well to assign a lot of them without clogging them up with weird combos

[PKG]

@Folliful

General Shortcut Keys in LibreOffice