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Silverlight Plugin not found on Mac OS Mojave using Firefox ESR 52.1.0

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I am using Firefox ESR 52.1.0 on a MacBook. I was on Mac OS High Sierra and then Silverlight was working on Safari until I installed Safari 12. At that point Firefox ESR 52.1.0 still ran Silverlight. I along with other users of a company Silverlight application have updated to Mac OS Mojave. All of the Apple documentation I have found notes that Safari no longer supports NPAPI but doesn't say anything else about the Mac OS Mojave blocking other applications from using these types of plugins.

Can you shed any light around Silverlight being completely dead on Mac OS Mojave users? I'm hoping there is some sort of workaround.

Thanks!

I am using Firefox ESR 52.1.0 on a MacBook. I was on Mac OS High Sierra and then Silverlight was working on Safari until I installed Safari 12. At that point Firefox ESR 52.1.0 still ran Silverlight. I along with other users of a company Silverlight application have updated to Mac OS Mojave. All of the Apple documentation I have found notes that Safari no longer supports NPAPI but doesn't say anything else about the Mac OS Mojave blocking other applications from using these types of plugins. Can you shed any light around Silverlight being completely dead on Mac OS Mojave users? I'm hoping there is some sort of workaround. Thanks!

Asịsa ahọpụtara

To those coming across this issue in need of an answer see this thread. https://discussions.apple.com/message/33934025?replyId=33934630#33934630

It appears MacOS Mojave and Firefox 52.9.0 ESR run Silverlight!

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Silverlight is a Microsoft product for questions on it you should contact Microsoft about their software.

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Asịsa Ahọpụtara

To those coming across this issue in need of an answer see this thread. https://discussions.apple.com/message/33934025?replyId=33934630#33934630

It appears MacOS Mojave and Firefox 52.9.0 ESR run Silverlight!

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Firefox 52.1.0 ESR was a old version from April 19, 2017. https://www.mozilla.org/firefox/releases/

The 52.9.0 ESR was the last for the legacy Firefox 52 ESR and is now End Of Life or EOL as of Sept 5 when Firefox 62.0 and 60.2.0esr were Released. There will be no more security and allowed stability updates for Firefox 52.0 ESR.


https://support.mozilla.org/en-US/kb/npapi-plugins The article does not mention 52.9.0esr anymore since it is EOL.

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Totally understand the security aspect of it. Our hope was get everyone using a Windows 10 PC as we know Internet Explorer will support Silverlight until we have time to re write the application.