How to screencast a url?

[ariel-frischer]

Any examples with screenshots or screencasting? Also does screencasting support recording with an alpha channel? (like to webm or mov format)?

[blueimp]

Yes you can create a screen recording of loading a specific URL.
While the project's purpose is to provide a Docker setup for Webdriver.io, it also comes with integration for video recording.

You can enable video recordings in the browser configs. For Firefox it's enabled by default:

wdio/conf/firefox.js

Line 18 in 77b7c95

enabled: true,

There's in example in the test specs how to save and diff screenshots.

The package providing the screen recording and diffing integration has more usage examples:
https://github.com/blueimp/wdio-screen-commands#usage

There is no support for alpha channel screen recordings.