Well, al sorts of mayhem happened after I upgraded 0.9.2.7 (via 0.9.2.6).
Normally I do not upgrade so hastily after an upgrade of a core plugin, but the fixed vulnerabilities made me decide otherwise.
Things I encountered:
- Warnings about file permissions. In 0.9.2.6 it was impossible to make those disappear, 0.9.2.7. fixed that.
- A lot of proposed additions to .htaccess (in different folders)
- Minify breaking
- Not possible to save anything anymore. It just did not remember the settings.
- The site started to behave strange, other applications on the server started to go nuts as well. This seemed to be database related.
In the end I decided for an (almost) complete reinstall, with me manually removing the directories and files in the root of the wp-content/ dir. I did not clean the database.
After that, the reinstall went smooth and things went back to normal, but after a few minutes the database problems started to appear again.
In the end, that was caused by W3tc filling up the /tmp folder, which explained the database problems (as mysql also uses it). I cleaned it, and after that everything was running smoothly again, except for the minification of js. Those files are created on disk, but the links that are created in the html give a 404.
If I can avoid it I will not upgrade so soon anymore. But I felt forced to do it because of the security fixes.
Maybe, Frederic, in the future you could separate the bare essentials to fix the vulnerabilities from the extra functionality. Although in this case, just fixing the security issues probably also was a major overhaul.