Additional plugins are required issue in Firefox with Forms 11g

At the time of writing this post, Oracle Forms 11g installations are configured by default to work with a specific JPI (Java Plug-In) version: 1.6.0_12.

You can verify this by checking your formsweb.cfg file:

grep jpi-version formsweb.cfg
#jpi_mimetype=application/x-java-applet;jpi-version=1.6.0_12

Unfortunately, it seems Firefox is very particular when it comes to JPI versions, and it will only run with the version specified in your configuration.  Internet Explorer and Chrome browsers however, seem to cope with other versions just fine.  So when you trying loading an 11g form in Firefox, and it tries to load the Java applet, you get the following messages:

Additional plugins are required to display all the media on this page.  Install Missing Plugins…

Now you could just install install JRE (Java Run-time Environment) 1.6 update 12, which contains the JPI, but a better solution would be to remove the restriction on a JPI version from your configuration like so:

export DOMAIN_HOME=/u01/app/oracle/middleware/user_projects/domains/ClassicDomain
cd $DOMAIN_HOME/config/fmwconfig/servers/WLS_FORMS/applications/formsapp_11.1.2/config
cp formsweb.cfg formsweb.cfg.DDMMYYYY
vi formsweb.cfg

Comment out the jpi-version reference:

#jpi_mimetype=application/x-java-applet;jpi-version=1.6.0_12

…and add the following line:

jpi_mimetype=application/x-java-applet

Save the formsweb.cfg file (no restarts necessary).

Next time Firefox tries to load the Java applet for your form, it will the JPI you have installed