How to fix “mutation operation” errors in Firefox

You may find at some point using firefox you are unable to access some websites which rely on complex javascript libraries. When you look at the errors on the page, you see:

“A mutation operation was attempted on a database that did not allow mutations”

The solution is to make sure dom.indexedDB.enabled is set to true in about:config

One example of a website with this problem is weather.com which will not display anything on the page unless this setting is enabled. Developers should wrap such function calls in try/catch or other error handling so your entire website doesn’t fail. Browser sniffing is not adequate.