Selenium passes on dev box, fails on Travis: page start’s javascript acts differently

I’m having an issue where the selenium based tests I have run fine locally, but fail on Travis.

Example build:

Git repo:
(note the webserver-work branch)

For some reason it appears as though some DOM elements are adjusted with the page start’s javascript, and some are not, causing the issue.

Any gotchas/ things to know when using Selenium on Travis?

Unfortunately I can’t see the full logs, so it is hard to debug these issues only seen on Travis… is the official doc on browser testing. I guess if you are using a framebuffer, the layout is going to depend on its resolution. Also check versions of the stuff in use. If it passes locally but fails in Travis, there must be a discrepancy somewhere.

You can upload full logs somewhere for examination. E.g. see Linking against ncurses, no package from Chocolately yet on how to upload to an FTP server.
Alternatively, you can request debug mode.

Thanks for the points! I put in to explicitly ask for a large screen size, but what ended up fixing it was explicitly telling the firefox driver to run in headless mode.