I embedded a dashboard from Tableau Public in my static blog built with Jekyll and hosted on GitHub. I was tweaking the viz settings in Tableau, saving, overwriting the copy on Tableau Public, and refreshing the locally served site in Firefox to see the results. Was working fine for a while but then all of a sudden the viz disappeared, both for the locally served site and the live site at username.github.io. Thankfully, both local and live site display the viz just fine when loaded in Safari, Chrome, and Opera. But I feel the need to solve this Firefox mystery. The site is to showcase my portfolio to potential employers and I do not want to clutter it up with a disclaimer about Firefox.
Btw, I discovered the bug was browser-specific and not related to my code when I went back to this tutorial and saw that Firefox was not loading their demo embedded viz, which it had been displaying just fine previously.
Your insight is greatly appreciated!
That viz from the tutorial is showing up just fine on my Firefox on Linux. I think your plugins are causing trouble. Just disable all plugins and try again.