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Firefox Developer 64 bits can't use Microsoft Silverlight (64 bits) and Java 8 (64 bits)

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  • Last reply by James

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I'm using Firefox Developer (42.0a2 (2015-08-26)). I've installed Silverlight (64 bits) and Java 8 (64 bit) but I can't use any web that use Silverlight or Java.

I'm using Firefox Developer (42.0a2 (2015-08-26)). I've installed Silverlight (64 bits) and Java 8 (64 bit) but I can't use any web that use Silverlight or Java.
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hi, 64bit versions of firefox on windows will only support flash as npapi plugin. if you want to use other plugins as well you'd have to continue to use regular 32bit builds. this is by design, as mozilla wants to take a clean slate approach to plugins on win 64bit apparently: https://wiki.mozilla.org/Firefox/win64/meetingarchive#Clean_Slate_Approach

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Sorry it does not work with those yet.

For 64bit Firefox for Windows only the 64 bit Flash plugin can be used. If you need to use other plugins use the standard 32 bit Firefox with 32 bit plugins.

Whether this will change in the near future or not I do not know, I have not followed the issue too closely.


For ordinary users Firefox for Windows is a 32bit browser and need 32 bit or 32 bit compatible plugins.

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Can I use 64 bits plugins in Firefox Beta 64 bits? I have to use Java 64 bits with other software.

Modified by Illuminator

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Chosen Solution

hi, 64bit versions of firefox on windows will only support flash as npapi plugin. if you want to use other plugins as well you'd have to continue to use regular 32bit builds. this is by design, as mozilla wants to take a clean slate approach to plugins on win 64bit apparently: https://wiki.mozilla.org/Firefox/win64/meetingarchive#Clean_Slate_Approach

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Thank to Jonn99 and philipp. Hope to see Sliverlight support soon :)

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Yes Win64 Firefox as of 41.0+ will only have the 64-bit Flash Player white listed currently.

The 64-bit Mac OSX and Linux builds can still use any available 64-bit npapi plugins for the os.