Display throbber as a visual feedback for like/post/save actions

[urbansheep]

Make background process more evident

We currently show a throbber when expanding a comment thread (and a big fat throbber for page load), but we have some more actions that might be non-instant, and need visual feedback to avoid double calls and user's frustration. Those are:

• Like/Un-like trigger
• Post/Save edited post
• Save settings

I propose that we add smaller throbbers, like in thread expansion mode, inline or in close proximity to the element, i.e:

• Show throbber inline to the right of the Like/Un-like link when it was triggered
• Show throbber in the margin to the left of the Post/Save buttons for posts and settings.

Rationale is that anyone who uses pepyatka on mobile, even on faster devices/networks, will benefit from feedback and subtle transparency.

Avoiding unnecessary jerkiness

Adding a throbber on fast terminal (be it due to fast network or fast hardware) might cause unnecessary movement for each of the actions. Thus throbbers might be deferred and displayed only when operation takes longer than 100-200 ms (i.e. not instant enough).

Another way to handle it is to add purely visual delay of 200-400ms as a minimum time threshold for throbber presence on the screen so that throbbers and changes fade in and out in an esthetically pleasing and comforting way, if throbber was actually triggered to appear. This will make things feel much smoother for the user.