Easier to be aware on a 64-BIT browser since many if not most plug-ins have no 64-BIT declination (yet) and that is, as far as I’m concerned, the last of my worries. I’m running Firefox 42 64-BIT and, if I use 64 (!) add-ons, I have not one plug-in installed. We are dealing with evidence, not with gadgets seemingly dressed up with a pseudo-improvement attitude in order to legitimate what is or can be an intrusion and/or a degradation of users’ liberty : NPAPI must no longer be supported, even as a “tolerance” interval to allow sites to move their a*s. I’m not a radical but there are times where a choice is incompatible with consensus. I believe browser developers should impose the natural course of technological evolution to websites and their administrators. I dislike the dilemma between audience and progress imposed by reluctant sites to adopt latest technology. I don’t use Silverlight, no more than Adobe’s Flash, I am of those who believe that html5 (browser capability to manage audio and video) is already a reality and fulfills tomorrow’s browser aims. That does not mean that they cannot protect their users by default, for instance by setting plugin contents to "click to play" instead of running them right away.
MICROSOFT SILVERLIGHT IN FIREFOX INSTALL
I think that browser developers should leave it up to the user to install and use plugins, provided that they don't cause instabilities or have known security vulnerabilities. Pale Moon for instance won't follow Mozilla, Google and Microsoft according to a post on the official forum. First, they can block updates of the browser to retain plugin functionality, or keep an older copy around for that purpose, or they may use a browser that won't discontinue support.
Neither Google with its Chrome browser nor Microsoft's new browser Edge support Silverlight anymore. It is interesting to note that Firefox is one of the few mainstream browsers left that supports Silverlight. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.This ends support for Silverlight and other browser plugins that depend on NPAPI in all versions of the Firefox web browser. The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Right-click the broken puzzle piece image, and then select Run this Plugin.
MICROSOFT SILVERLIGHT IN FIREFOX WINDOWS
In the Enable NPAPI Mac, Windows box, click Enable.On the address bar in Chrome, type chrome://flags/#enable-npapi.To work around this issue on versions 42 to 44 of Chrome, follow these steps: You must use a browser that supports Silverlight content to access a Silverlight page. It is not clear right now if the organization manages to add support of Silverlight in Firefox 43, to be released on December 15, 2015, or Firefox 44, which will be released on January 26, 2016. On Chrome version 45 or a later version of Chrome, there is no workaround for this issue. Mozilla plans to integrate support for Silverlight in 64-bit versions of Firefox in Firefox 43 or 44.
This issue occurs because these versions of Chrome block Netscape Plugin API (NPAPI) plugins from being displayed in the browser.
These browsers still support Silverlight content. This issue does not occur in Microsoft Internet Explorer, Mozilla Firefox, or Apple Safari.