Why Silverlight Won’t Work on Chrome


In early September, 2015 Google stopped supporting NPAPI technology on Chrome.  There are no workarounds.  This breaks software packages like Microsoft’s Silverlight, which in turns breaks applications like Fidelity’s web based version of Active Trader Pro.  Many other browsers still support NPAPI, but they (except for Microsoft) will probably follow Google’s lead and drop NPAPI support eventually.   Fidelity recommends switching to their client based version of Active Trader Pro.  I have done that and it seems to be working well, but unfortunately this is not a solution for people not using Windows based computers.



In early April I attempted to logon to Fidelity’s Active Trader Pro using my Chrome browser and I was greeted with:





I was pretty sure Silverlight was installed on my system, but I dutifully reinstalled it—and was informed that it was already installed.  Suspecting a browser issue I fired up Internet Explorer where Active Trader Pro ran correctly.

Investigation revealed that Google has decided to obsolete the old Netscape Plugin Application Interface (NPAPI) technology, which Silverlight relies on.   According to Google this change:

 …will improve Chrome’s security, speed, and stability as well as reduce complexity in the code base.

In April Google blocked all Chrome plugins using NPAPI by default but provided an override for advanced users.  That override is scheduled to go away in September 2015.

I used Fidelity’s chat line for recommendations on how to address this.   Their opening bid was for me to switch to Internet Explorer or Firefox.  I declined and asked if there was a workaround for Chrome.   The first step was to start up my Chrome browser and type “chrome://flags/” (no quotes) in the address bar and enter.   The resultant page:


Next I was instructed to search for NPAPI on this page; you can use the Search function (Ctrl +F) to do this.   The “Enable NPAPI” item was towards the bottom of the 1st page.   I clicked the enable link.

Next I was instructed to type “chrome://plugins” (no quotes) in the address bar and enter.   My plugin page looked like this:


On my system Silverlight showed up as the 3rd plug-in in the list.  I was instructed to click the enable link and check the “Always allowed to run” box.

At this point Active Trade Pro on Chrome worked.   The Fidelity representative warned that they have seen some problems with streaming information with this workaround, so be aware that streaming quotes might not be valid.

Google’s move puts Fidelity and others like them that use Silverlight in a difficult position—either force approximately 25% of their users to change browsers (Chrome’s current market share), or rewrite their code to not use Silverlake technology (e.g., switch to HTML5).  And they only have until September to get this done…

I’m with Google on this one. I’ve been involved with large software projects where old technologies have become an increasing source of complexity and performance issues.  It’s painful to move forward, but in the long run the user really benefits from obsoleting the old code.

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