Firefox does 'gah! your tab just crashed' on my amazon tabs at a rate of about 1 in every 4 times. Once it decides to do that on a particular tab, no amount of refresh or reopen, or restart-firefox fixes it.
I'm using Ubuntu 14.04, and this has been happening consistently for the last 5+ years.
Every. single. goshdarn. effing. firefox. release.
(sorry just wanted to vent. I've tried every solution I could find on askubuntu, stackoverflow, what not. Nothing fixes it. I know I should be filing a bug report, and/or upgrading my OS, but I don't have the time, patience to deal with that. I need to finish school first.).