Multiple selection of HTML elements in Firefox (or other) inspector?

Question

In the question https://stackoverflow.com/questions/33907611/controlling-line-spacing-with-br-firefox-rendering-differences-with-html4-doc , I wanted to show the boxes of HTML elements, as that would have clarified the problem best. Unfortunately, I couldn't find a way to select multiple elements when using the Firefox inspector, so I had to select each element individually, take a screenshot, and then combine the screenshots into an animated gif like this:

... which is a rather tedious and time-consuming job.

Is there a way to do a multiple selection - either from the main browser window, or from the HTML tree in the inspector in the bottom - such that the element boxes of the selected elements are all indicated/shown simultaneously? I tried Ctrl+click-ing, that doesn't work...

Alternatively, is there another addon/browser/tool that can do this (maybe Chrome?)

Answer 1

In going through the latest release of Google Developers' EDIT THE DOM section for Chrome, there is no mention of the ability to select multiple elements. This suggests the feature doesn't exist.

A similar question came to the same conclusion, albeit the link reference wasn't much help.

Thinking about it logically, however, there's really no way such a feature could reasonably work: Once an element is highlighted, dev tools (or Inspector) populates the right panel with the element's styles, computed values, event listeners, and other unique data. How could dev tools do this for two or more elements at a time? Maybe it's technically possible, but the appearance would be messy, cluttered and potentially confusing.