The display view layer icon is the exactly same to the one above, I propose merging the button with the filter icon to the right of the search bar
The search bar should be dynamic and responsive to the width of the outliner menu. This would make all the buttons viewable on smaller screens, instead of having to scroll to the right in order to add a new collection.
Lastly, the scene collections should be moved a bit to the left so it is centred with the current editor type.
That is not actually true. The one in the top bar changes the active view layer, while the one below changes the Outliner view mode.
That said, yes, this part of the UI could be made nicer.
Could do:
This would both simplify the UI, while adding clarity
Well, it’s the same icon but that’s kind of the point isn’t it ? They refer to the same thing, ie View Layers.
Great to see the Outliner will get some (more) love.
One thing that I would really love to see is the ability to use the Eyedropper tool in the Outliner to select objects. When a lot of geometry is sitting on top of each other it would be a lot easier to pick it from there rather than the viewport.
@Kranos The other part of synced selection is to sync the selection completely with the 3D view. That way whatever is selected in the outliner is selected in the viewport and vise versa. There will be a toggle to enable or disable synced selection in each outliner.
@Bobbin If you are referring to dragging on the disclosure triangles, I believe the devs are aware of this. ⚓ T57746 Outliner: Dragging over disclosure triangles moves item rather than opening/closing Thanks for bringing it up 
@Jomo About selecting materials and having it show up in the properties panel, that is part of synced selection. The priority is to sync the selection with the 3D view, and other editors will be added as time allows. During this week I plan to make a thorough plan of all features I intend to complete over the summer.
Also, selecting the hierarchy when selecting a collection is an interesting idea, though it may not be the most desired behavior at all times.
@MichaelHermann This is already planned, and won’t require the eyedropper tool. Synced selection will allow selecting objects in the outliner just by clicking/box select/etc.
Not sure if we are on the same page here. I’m not talking about selection at all. I don’t want to select anything. This is specifically about the eyedropper tool. (To pick a target object for the “Track To” constraint for example)
It currently only works in the viewport and it would be very nice if that were extended to the outliner. 
Sorry if you did mean this with your answer. But I hope this clarifies what I meant to ask for.
Oh that makes much more sense now. I’m not sure how the eyedropper tool works, but I think that may be outside the scope of the summer of code. I will add it to the list though because I think it is a great idea.
Awesome, thank you! 
Since “sync selected objects” between editors will be a target. I want to remember if could be possible to implement that in viewport we could filter and only show the objects that we see in the outliner after a search.
I think it can fit in fine, I expect it won’t be much work to implement this.
On a side note, I’m just now realizing the eyedropper does not have the ‘selection choice’ when doing alt+click, it would greatly benefit from this.
Great idea! That would be very helpful and also consistent with regular selections.
But tthis is not inherent to Outliner
Can we get a hotkey combo for changing the active object. Or make it consistent with the 3d viewport in that shift+clicking a selected object first makes it active without deselecting it?
There’s no easy way to change the active object from the outliner. If you’re in selected only view, and want to work on one of the objects it becomes even more important.
Dropping this here (sorry it has been posted before), taking it from how maya does it, which I have always found useful on big scenes:
| Expand or collapse the level under a node. | Click the plus  or minus  next to the node name. |
|---|---|
| Expand or collapse all levels under a node (quick way to see all nodes). | Shift + click the plus or minus next to the node name. |
The basic idea is that if you open or close a hierarchy of the outliner while keeping Shift pressed, it’ll collapse or expand all the child.
Of course, without Shift, simply expand and collapse retaining the previous settings.
My2c.
L.
This is current behaviour actually
Almost, it doesn’t open/close the level you click on:
I think all selections in the outliner should reflect on the viewport. Like when we select with box select and the items are still inactive on the viewport.
Hiding objects beneat the parent should be an option, a toggle. It’s confusing this way.
Please please please get rid of the useless left spacing. It’s bad when using narrow columns.
Good point, I never noticed that.
@GabrielMoro if you read the proposal you’ll find it is exactly what is being worked on : synced selection and a gutter on the left for box selection (although I’m not sure that one isn’t obsolete). Visibility inheritance is already there, with collections (not with parenting).
@Antaioz Yes, I am planning on making the selection mostly consistent with 3D view. The only exception I can think of will be Shift+click for range select rather than extend selection in the 3D view. But I feel it is more intuitive to have shift be for ranges because most file/list browsers use shift in that manner.
@lorenzoangeli as others have noted, this functionality is already in Blender (though it appears to not be as intuitive as it could be…) I’ll look into it
@L0Lock strange. Thanks for showing how it currently functions. I’ll look into this (and add it to the todo list)
