In Blender 2.8, it's not easy to select data-blocks to operate on them.
This is because clicking on a mesh (for example) activates them, which toggles edit-mode.
So if you want to select two or more meshes, for example, you can't shift-click to select them without toggling their modes.
Try perform an operation on 2 or more data-blocks, it's quite awkward.
In 2.7x, clicking on the icon/name switched modes, but clicking before on the row anywhere else only selected.
From what I can see there was never a decision to change this behavior, last discussed here T37430.
This patch allows selection without activating, as before.