the native “Solo” function is a very good tool…IF you remember you turned it on.
(It’s toggled with hotkey “/”.)
Is there any indicator that it is ON when it is on? Because I just lost five minutes scrambling around to find an Object…
Consider this a Feature Request if not.
(I’d do something similar to AE’s “red border around vuport” technique for when the user has pressed CAPSLOCK to suspend vuport updating — OR I’d use the Blender Outliner’s existing eyeball icons.)
Top left corner of viewport will have “(Local)” when you’re in local view.
@Stan_Pancakes just beat me to it, but here’s a screenshot:
Thanks for that tip. 
Seems a bit of a bad word choice, since it ‘collides’ with the coordinate system label “Local”, which is what I assumed it was referring to.
There are quite a few of those (questionable nomenclature). Some of these, like Local View, go way back to times when there weren’t common established names for such things. Just like some of the UI is still rooted in decisions made a couple of decades ago 
::cough:: You don’t say! 
FWIW, I wish they’d just use the Eyeball indicators that already exist.
'Tis not that simple. Reusing those indicators will conflict with hiding of objects.
I didn’t mean my comment as a joke: there are legacy UX issues that aren’t easily (quickly) fixed/changed/removed given how Blender’s development is structured.
