With firefox 15.0 and "click to play" set to true,
java applets no longer work (for all web pages with java applets I've tested):
With "click to play" enabled,
"click here to activate plugin" should be displayed instead of any applet.
This works fine e.g. for flash applets,
after clicking the flash plugin starts to play.
For java applets,
"A plugin is needed to display this content. Install plugin..."
is displayed instead (strange, because the applet is installed, see below!),
but even after clicking, the plugin does not play (installation fails).
When "click to play" is disabled, java applets work fine
(hence, the java plugin is installed correctly,
is detected by firefox, and works).
Tested with both dev-java/icedtea-bin 184.108.40.206
and dev-java/oracle-jdk-bin 220.127.116.11,
Works with current versions.