Jan 10 2016
FYI, a completely fresh install is working fine, so clearly this is either (a) a clash with something existing loaded in localsettings.php or (b) a problem in the upgrade process.
As others reported, chrome/edge console reports the following error -
scratch that about uploads working - they're not any more -
It's windows\temp and has write permissions. file uploads are working, so don't think that's the problem. Where can I found out more about the less implementation, since that seems to be where it's happened? Trying to implement a vector-based skin (metro) and it does the same thing not surprisingly.
Same issue, 1.26 on IIS8 with PHP5.6. I have open_basedir disabled. MW is successfully creating a file I10n_cache-en.cdb in the cache directory, so that doesn't seem to be the issue.