focus can be given to Everything
- without Everything having focus

i believe it will have to do with an overflow condition
- say of the /name/ field...
say you've got a mp3 playing (in your mp3 player), right-hand side of screen
Everything is open, left-hand side of screen
mp3 player has focus
move mouse cursor over Everything window (do not click)
move mouse cursor over an overflow item
- because it is an overflow item, & because mouse is hovering the item, Everything will display the item including overflow data
now, /gently/ click on that item (actually, it doesn't even need to be too gentle)
- at that point, item is highlighted
BUT
notice that /focus/ is actually still on mp3 player
& that Everything does not show it to be focused
mouse cursor is still over Everything
overflow item is highlighted in Everything
press a mp3 player hotkey (say F8, on my end, Next item in playlist)
mp3 player plays the next song
no big deal, & it is an odd occurrence, but i guess it could have undesired consequences
say if you hit the DEL key, expecting to delete (highlighted) file in Everything,
& instead some other program reads that DEL keys & (hard) deletes... something...
(Reminds me of a Mozilla bug..., here, Bug 1554490 Firefox is not focused on first open of a NEW Profile.)