I have a Firefox extension that supports Firefox 3+, and SQLite database is important for my extension. I saw on the MDN that the API might change and it`s “unfrozen”, should I be worried about it?
The API is currently “unfrozen”, which means it is subject to change
at any time; in fact, it has changed somewhat with each release of
Firefox since it was introduced, and will likely continue to do so for
a while.
This warning is probably outdated, it has been added to the original version of the document years ago and hasn’t been updated since. Fact is, starting with Firefox 4 all APIs are unfrozen and could change. But that shouldn’t really be a reason to worry. As SQLite access goes, the API seems pretty mature by now and Mozilla developers are mostly tweaking performance without introducing breaking changes. The most important change was the introduction of asynchronous API in Firefox 3.5 and the deprecation of the synchronous API. But as long as you only use asynchronous API you should be on the safe side (I cannot imagine that you really need to support the ancient Firefox 3.0 release, I guess that you actually meant Firefox 3.6).