Can Babel be made an optional component for 0.12?

Sure, already did so for a number of plugins.

I need to look into the source and apply changes needed i.e. to retain the locale directory in packages even without compiled message catalogs and make sure that translation helpers really fallback gracefully in situations without Babel installed.

Thanks for pointing out this weakness. I accept this as complaint about an obvious regression. Babel is not hard to install, but OTOH it is still optional in Trac these days, no question. BTW, the requested changes are needed for re-gaining backwards-compatibility down to Trac 0.11 too, and it's not too hard.

Beware, that I pulled WikiTicketCalendarMacro development (back) to WikiCalendarMacro. (We even talked about it some time ago, didn't we?) While I'm currently not completely satisfied with trunk code, it is nonetheless running well - for me - with Trac 0.13dev, now providing both macros, better user input sanitization and unicode support, and should do equally well at least with Trac 0.12 too.

Replying to hasienda:

Thanks for pointing out this weakness. I accept this as complaint about an obvious

regression.

Had I been paying more attention I would have reported this as an enhancement, but thanks for accepting the feedback anyway.

Beware, that I pulled WikiTicketCalendarMacro development (back) to WikiCalendarMacro. (We even talked about it some time ago, didn't we?) While I'm currently not completely satisfied with trunk code, it is nonetheless running well - for me - with Trac 0.13dev, now providing both macros, better user input sanitization and unicode support, and should do equally well at least with Trac 0.12 too.

I'm in the process of a Trac 0.11.7 -> 0.12.2 switch over. I hope to have that completed by the end of the weekend. I'll be able to do lots of testing on 0.12.2 for you.

(In [10985]) WikiCalendarMacro: Apply fix for packaging without compiled message catalogs, refs #9568.

Similar issues existed for AccountManagerPlugin (#7850), TagsPlugin (#7787) and others before. Previous code (done by me) was just too inconvenient and didn't respect current Trac policy to still treat Babel as optional dependency.

Other, not striktly related changes are just more steps towards next release. This includes especially ongoing documentation of changes.

I'm up and running now. I'll report back after I've done some additional testing. Thanks!

(In [11557]) WikiCalendarMacro: Try header localization according to user pref, refs #7564 and #9568.

Calendar headers are localized according to user preference, if the server has suitable locales installed. Unrelated micro-improvement: CSS tooltip text is slightly magnified now.