An (almost) brand new installation. I've just added a few "regular desktop" apps via apt-get and installed Google Chrome. I can see the link in the page source, so I can continue.
Same here, tested on Chrome, Firefox, and Opera in Windows. The button has a size of 0x0 pixels because it's a link without content and is displayed inline. Maybe a test for developer competence :-(
Thanks for the feedback. I've rewritten the codelab from scratch and believe I have fixed this issue. The code has been updated, and the new guide is now live.
If you find any issues with the new codelab, please let us know!
An (almost) brand new installation. I've just added a few "regular desktop" apps via apt-get and installed Google Chrome. I can see the link in the page source, so I can continue.