Here is the release manager's (KennethLavrsen) reflection on TWiki 4.2.1
As release manager for TWiki for almost 3 years I have been managing the releases of quite many TWiki versions now.
But the release 4.2.1 is probably the release I have put more heart and energy into and also the release I have felt most pleased with getting finished and made available for our many users.
TWiki release 4.2.0 was a significant release feature wise. It introduced a fantastic new Wysiwyg editor. It introduced the query search which greatly increases the possibilities for the application builder. And it introduced a major code re-factoring that enables adding external user mappers, so you can have a common user database with other applications. But with new features comes new bugs. Most of these bugs were quickly fixed but a few were very hard and time consuming to fix.
The typical situation is that bugs marked urgent get a lot of attention while the normal and low priority tends to pile up. But for 4.2.1 we were a few that decided to attack the Normal and Low priority bugs to bring down the backlog and the result is that 4.2.1 closes more than 150 bugs of which many were several years old. I am proud to know that I personally closed more than 50 bugs.
So what is in it for the users? Should I upgrade? The answer is very much Yes! No doubt.
The Wysiwyg editor is a much more nice experience than it was in 4.2.0. The user will experience much better stability and much less random corruption. Attachment feature now finally works inside the Wysiwyg editor.
For non-English speakers TWiki 4.2.1 handles non-english characters much better. Especially in the Wysiwyg editor. TWiki has moved towards better support for utf-8. TWiki is not yet fully supporting utf-8 but especially Chinese/Japanese/Korean users can have an advantage of trying to use utf-8. This however requires a manual conversion of existing topics to utf-8. The better international support unfortunately also means that we have had to give up support for the old Perl 5.6. Latin type languages are much better off using iso-8859 character sets (default).
EditTablePlugin has been known to not preserve Twiki variables as variables but instead save their value. This has prevented many twiki applications to take full advantage of the plugin. This is now fixed making EditTablePlugin a really cool plugin.
Perl 5.10 has hit the street and is now part of newer Linux distributions. TWiki 4.2.1 has been tested with 5.10 and a few bugs have been fixed to make it work with 5.10. Installers should pay attention to the release note related to specific versions of the CGI CPAN lib which are broken and needs to be upgraded on some perl 5.10 installations.
Finally the user mapping (maps login name to wikiname) has been fixed. You can now again use login names in access rights settings. There was a bug related to login names containing non A-Z0-9 characters in 4.2.0 which in rare cases (requires an unusual but possible use of TWiki) could allow an attacker to take the identity of another user. Additionally the bug did not encode non-English characters correctly. This is all resolved in 4.2.1. If you have setup TWiki 4.2.0 to allow login names containing characters '_@.-' it is vital that you upgrade as soon as possible.
Upgrading 4.2.0 to 4.2.1 is easy!
Take a back up of your running installation. Download the upgrade package from the TWikiRelease04x02x01 page and throw it on top of your running installation. The upgrade package does not contain the files that an admin typically tailor. Note that TWiki.TWikiPreferences will be overwritten so if you edited this (not recommended - always move settings to Main.TWikiPreferences) you should first move altered settings to Main.TWikiPreferences before you apply the upgrade package. An upgrade of a TWiki 4.2.0 to 4.2.1 may only take 15 minutes unless you have modified an unusual amount of things yourself.
Enjoy 4.2.1. We put a lot of hard work into it for 7 months.