Hi all,
by now I am used to the idea that blender -as great an application as it is- has some veeery counter intuitive quirks so I never know if I am doing something wrong or it’s Blender’s stubbornness…
whenever I have just one object selected, I press M and move it to a collection but for some reason, when I select multiple, this command cannot be selected.
RC2 means Release Candidate 2. there is a small chance that if you are using 2.8 RC1 (first release candidate) that the bug was fixed with the latest RC2…
So try downloading RC2 version (currently on main page of Blender) and then see if the big persissts, then indeed report bug if it does)
It looks like you have selected them but none is active (yellow outlined).
For me when one of the selected objects is active “move to collection” works.
Maybe blender is trying to keep you from “moving the active but not visible” object by mistake.