Hmm, I'm not really sure that we really need such a thing as an 'opera-next.tcz' extension (in particular one that shows on it's own 'about:opera' page that it is only "pre-alpha").
The Opera team is pushing out their "bleeding edge" releases fairly frequently (sometimes multiple times in a week) and announce them via their
blog. In my view calling it now 'Opera-next' instead of an alpha or beta release is just the "flavour of the month" following in the trails of Chrome and FireFox with their different "channels" etc.
Looking at the repository where I can spot an outdated 'firefox-beta.tcz' (of v4.0rc1) whilst the (stable) 'firefox.tcz' is v5.0.1 just shows (at least IMHO) how futile it can be trying to chase more than just a current stable browser release.
My suggestion would be to remove the outdated 'firefox-beta.tcz' and not include an 'opera-next.tcz' in the repository. I could see the point in having something like "FF-beta" when the development cycle was considerably longer (e.g. 13 month between FF 3.6 and FF 4.0), but nowadays in the current climate of much shorter "gestation" periods, I'm not so sure about that.
I'm aware that there exists a "hidden" 'opera11.tcz' extension in the repository. As far as I can tell it is hidden as it lacks an 'opera11.tcz.info' file (which prevents it's inclusion in 'info.lst'). That is not a big loss in my view as it contains the already outdated release 11.11 as the current stable release is 11.50. It might be worthwhile to create a "proper", up-to-date 'opera11.tcz' extension.
On that note I wonder why the latest stable release should not be called 'opera.tcz' and the (trusted) old 'opera.tcz' (i.e. v9.64) be renamed to 'opera9.tcz'. I'd like to think that would be more reasonable, as it might surprise some users that something that is more than two years old pretends to be "fresh". Furthermore I don't really see a need for keeping a 'opera10.tcz' extension around, as that was IMHO anyway not such a great effort.
For those (presumably few) users that want to trial the Opera alpha or beta releases this process has since about a year been pretty simple: download, extract, (install the one or two dependencies like 'libxft.tcz') and just run it (e.g. in the extraction directory). Sure that is not automatically persistent, but there were quite some "dud" releases that did not quite work, so who wants those to be an extension? Plus the overhead for the repository maintainers with that sort of churn might not really be required.
OTOH, for users that want to create a (private ?) extension I'm attaching here a script that could be used to create such. It just requires to either change some variables at the top of the script or call it with a suitable URL (for downloading a new release) as parameter. It should then be able to create an appropriately named extension (plus a '*-locale.tcz' one).
Note: It has been successfully tested against the current stable (i.e. v11.50) and 'opera-next' releases, but I'm not sure for how long that will be the case into the future.
EDIT 1: As I tried to upload a 2834 bytes script I've received a
The upload folder is full. Please try a smaller file and/or contact an administrator. message back from the SMF system. So I'm going to attach the script later ...
EDIT 2: The script has now been attached and a silly misspelling corrected.