Dear colleagues in misfortune, unfortunately I have no suggestion for improvement, I was just looking for a solution in a frenzy of frustration and came across your comments, I just wanted to share my sympathy. I wonder if the three (also completely useless to me) Bluetooth connectivity buttons couldn't at least be made configurable through a software & firmware customisation, it would already be a massive improvement. I hope that at some point there will be an MX Keys 2 where Logitech will reverse these dodgy design decisions, I'd buy it in a heartbeat as I really love the keyboard otherwise

One of the biggest disadvantages of this keyboard: No standard layout. Instead, space is senselessly wasted above the arrow keys, where the source device keys could also have been placed (for example).
I used AutoHotKey to put the three missing keys, like Pause / Break, on the three keys above the numeric keypad to avoid having to do Fn operations. (But this is only recommended for those who are IT-savvy.) It probably also works with the Options+ software.

i agree ...... endless bells and whistles .... and keys, some of which have 4 symbols.... and all i wanted was an ergonomic, elegant wireless keyboard.......... some of the keys have symbols... that i've never seen before...... i really don't want to read the instructions here to understand it all ....... Less is often more!

Normally, the break/pause button is located above the "Page Up" (in the block of 6, not on the right in the numeric keypad).