[TYPO3-dev] [Typo3-Dev] indiscriminate of i18n and languages in typo3.

[Michael Scharkow]

Dennis Cheung wrote:
> Hi Kazper,
> 
> How will 4.0 backwards compatible to 3.8?
> I mean, who will not able to upgrade?
> 
> I know typo3 since 3.8. But I see there are still have many
> incompatible to 3.5 version. (e.g. user auth service). 

TYPO3 has been for most of the time been backwards-compatible, so that 
you could update your 3.x to 3.y without much trouble.

However, if an extension uses a feature of 3.y, you cannot use it with 
any < 3.y core version. This feature is called upwards-compatible and is 
*not* followed in TYPO3 development.

I am very eagerly awaiting a 5.0 branch where we can get rid of *all* 
the old compat-cruft, but that won't happen until after 4.5 I guess.

Greetings,
Michael