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OSX 10.8.3 + Firefox 21/22/Nightly (new install + new profile) does not launch jnlp correctly. FF 20 does. Known issue?

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  • Last reply by umlungu

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When browsing to a java applet launched via JNLP, FF 21/22/Nightly will not load and deploy the java applet correctly, but FF 20 does. I have tried the following things:

- Install/Uninstall/Install Java 7 Update 21 - Disable/Enable Java plugin in all browsers - Repair Disk Permissions - Always use new FF profile - Clear Recent History / Reset Firefox - Clear Java Cache

One additional piece of information is that the jar has mixed code signatures. FF20 prompts the user to "Block / Don't Block" the code from executing, but FF21+ does not.

I have also tried signing the code as well as setting the Java preference to disable mixed code signature verification, without success.

Any other thoughts?

When browsing to a java applet launched via JNLP, FF 21/22/Nightly will not load and deploy the java applet correctly, but FF 20 does. I have tried the following things: - Install/Uninstall/Install Java 7 Update 21 - Disable/Enable Java plugin in all browsers - Repair Disk Permissions - Always use new FF profile - Clear Recent History / Reset Firefox - Clear Java Cache One additional piece of information is that the jar has mixed code signatures. FF20 prompts the user to "Block / Don't Block" the code from executing, but FF21+ does not. I have also tried signing the code as well as setting the Java preference to disable mixed code signature verification, without success. Any other thoughts?

All Replies (7)

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Hello,

Try Firefox Safe Mode to see if the problem goes away. Safe Mode is a troubleshooting mode, which disables most add-ons.

(If you're not using it, switch to the Default theme.)

  • You can open Firefox 4.0+ in Safe Mode by holding the Shift key when you open the Firefox desktop or Start menu shortcut.
  • Or open the Help menu and click on the Restart with Add-ons Disabled... menu item while Firefox is running.

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article for that.

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help other users who have the same problem.

Thank you.

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Do you have the Java Web Start application installed that can handle the application/x-java-jnlp-file MIME type?

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Thanks for the suggestion amitshree. Safe Mode produces the same results as non-safe mode. FF20 works beautifully, but FF21+ does not.

Any other thoughts are greatly appreciated.

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Thanks for the suggestion cor-el. Yes, I have Java Web Start installed and I confirmed the mime type associations are correct in all versions of Firefox I am testing with.

One other point. I read in the Java 7 Update 21 release notes that there is a known issue with launching JNLPs in browsers when the server has a specific nocache http response header set on the JARs. I have confirmed this is not the case.

Any other thoughts or suggestions are greatly appreciated.

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Did you check the JNLP setting in the Java Control Panel (Advanced tab)?

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Yes, thanks for the thought. I have tried both "Prompt User and Always Allow" with the same results.

As I said it's working fine in Firefox v20, but 21+ is a no go.

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Another follow up to this topic.

It appears that in FF21+ javascript can not communicate with in-page applets. FF20 on OSX as well as FF21 on Windows are able to, but not FF21+ on OSX.