In previous W3 Total Cache versions, rules for the Nginx server were not correct when the option “Prevent caching of objects after settings change” in Performance > Browser Cache > General was enabled along with “Rewrite URL structure of objects”. Having both of these enabled caused PHP fallback to be used for all minify assets when utilizing the Disk: Enhanced page cache engine.
W3 Total Cache 0.12.0 removes “location” block conflicts for URL postfix rewrites and adds header directives for all other “location” blocks.
In 0.12. version security headers will also work correctly now, which wasn’t the case before as Minify set to disk was not rewriting when Browser Cache with Prevent Object Caching was used in Nginx
That change may, however, due to problems on some systems using non-default WordPress rules so keep a backup of your original rules to ensure you minimize issues.
Particularly WordPress Networks (WPMU) deployed in subfolders instead of in the root directory of the domain, i.e. myhost.com/myfolder/ for WordPress set up and myhost.com/myfolder/my-blog2/ for subdirectory network blogs.