DOM event precedence

This was not, so far as i know, explicitly defined in the past. Different browsers are free to implement event ordering however they see fit. While most are close enough for all practical purposes, there have been and continue to be some odd edge cases where browsers differ somewhat (and, of course, the many more cases where certain browsers fail to send certain events at all).

That said, the HTML 5 draft recommendation does make an attempt to specify how events will be queued and dispatched - the event loop:

To coordinate events, user interaction, scripts, rendering, networking, and so forth, user agents must use event loops as described in this section.

There must be at least one event loop per user agent, and at most one event loop per unit of related similar-origin browsing contexts.

An event loop has one or more task queues. A task queue is an ordered list of tasks [...] When a user agent is to queue a task, it must add the given task to one of the task queues of the relevant event loop. All the tasks from one particular task source must always be added to the same task queue, but tasks from different task sources may be placed in different task queues. [...]

[...]a user agent could have one task queue for mouse and key events (the user interaction task source), and another for everything else. The user agent could then give keyboard and mouse events preference over other tasks three quarters of the time, keeping the interface responsive but not starving other task queues, and never processing events from any one task source out of order. [...]

Note that last bit: it is up to the browser implementation to determine which events will be grouped together and processed in order, as well as the priority given to any particular type of event. Therefore, there's little reason to expect all browsers to dispatch all events in a fixed order, now or in the future.

For anyone wanting to know the sequence relative events get called in, see below. So far I have only tested in Chrome.

1. mouseover
2. mousemove
3. mouseout

1. mousedown
2. change (on focused input)
3. blur (on focused element)
4. focus
5. mouseup
6. click
7. dblclick

1. keydown
2. keypress
3. keyup

If you're looking at mouse/touch events, Patrick H. Lauke has published a talk on the subject. Definitely an interesting read – and deals with all the quirks of different browsers, different devices and different standards.

He also bundles a comprehensive set of tests.

Here is demo for a number of events:

<input  onclick="console.log('onclick - Mouse clicks an object')" 
     ondblclick="console.log('ondblclick - Mouse double-clicks an object')"
    onmousedown="console.log('onmousedown - A mouse button is pressed')"
      onmouseup="console.log('onmouseup - A mouse button is released')"
    onmousemove="console.log('onmousemove - The mouse is moved')"
   onmouseenter="console.log('onmousenter - The mouse is moved over an element (not bubbling)')"
    onmouseover="console.log('onmouseover - The mouse is moved over an element')"
     onmouseout="console.log('onmouseout - The mouse is moved off an element')"
   onmouseleave="console.log('onmouseout - The mouse is moved off an element (not bubbling)')"
       onchange="console.log('onchange - The user changes the content of a field')"
      onfocusin="console.log('onfocusin - An element gets focus')"
        onfocus="console.log('onfocus - An element gets focus (not bubbling)')"
      onkeydown="console.log('onkeydown - A keyboard key is pressed')"
     onkeypress="console.log('onkeypress - A keyboard key is pressed or held down')"
onselectionchange="console.log('onselectionchange - The caret position changed')"
        onkeyup="console.log('onkeyup - A keyboard key is released')"
       onselect="console.log('onselect - Text is selected')"
     onfocusout="console.log('onfocusout - Loosing focus')"
         onblur="console.log('onblur - Loosing focus (not bubbling)')"
   ontouchstart="console.log('ontouchstart')"
    ontouchmove="console.log('ontouchmove')"
     ontouchend="console.log('ontouchend')"
  ontouchcancel="console.log('ontouchcancel')"
    placeholder="edit me"
/>

I noticed that on chrome/firefox desktop onselectionchange fired before onkey, while it was the other way around on android chrome.

https://jsfiddle.net/yv8zg5d1