Google first announced their plan to deprecate support for Silverlight in their Chrome web browser last year, and they recently reaffirmed this decision with specific timelines. Support for Silverlight inside Chrome will see deprecation starting in January 2015, with workarounds ending in April 2015. When we blogged about this in late 2013, we mentioned the possibility that either (a) Google might push their timelines out; or (b) Microsoft might come with a solution. At the same time, we reaffirmed our commitment to HTML5, open standards, and a transition plan for moving off Silverlight. Before we talk about paths forward and the future, let’s discuss the current facts.

The majority of our customers have either transitioned onto our HTML5 technology or are already working through a transition plan. If you aren’t currently deploying applications using Silverlight, or your users don’t use Google Chrome (Internet Explorer will continue to work for years to come and Firefox already has a degraded experience), these specific upcoming changes won’t affect you. However, given the tremendous benefits of HTML5 (e.g. no plugins, cross platform support) we encourage you to prioritize HTML-based applications in 2015 regardless.

Here’s a reminder of what’s happening over the next few months:

  1. Sometime in January 2015, Google will release a version of Chrome that will prompt users to enable Silverlight when accessing a Silverlight application. Once enabled, the setting should stay indefinitely, and the user won’t be asked again. This is very similar to the functionality seen today in Firefox.
  2. Following that change, sometime in April 2015, Google will roll out another update that will disable Silverlight from running in Chrome entirely.  At this point, it will be technically possible to override this behavior in Chrome’s settings, but the average end user can’t be expected to do this.
  3. Finally, sometime around September 2015, Chrome will completely lose the ability to run Silverlight with no way to override.  While the September date gives a sliver of hope for running Silverlight applications on Chrome later into 2015, our advice is to work towards the January date while keeping the April date as a drop-dead backup plan.

Our goal is to engineer technology to make adaptation to change (desirable or otherwise) as straightforward as possible. Our Geocortex Viewer for HTML5 – together with our workflow technology – make up the key transition strategy for those who have built applications with Silverlight. Over the last year we’ve been extremely focused on building out comparable functionality in our HTML5 viewer; in the first months of 2015, we’re scheduled to release Geocortex Viewer for HTML5 2.4, which we anticipate will cover the vast majority of functionality that is actively deployed in our Silverlight viewer.

For some, standing up a parallel HTML5 application has taken only hours or a few days; for others it can be more time consuming, depending on the level of customization required. If you haven’t already done so, we strongly encourage you to begin heading down this path soon.

Recognizing that a full transition to HTML5 can take some time, we’ve set up a number of resources that you can take advantage of immediately to minimize disruptions to your existing Silverlight applications. Please visit http://www.geocortex.com/silverlight-to-html5 where you’ll find the following:

  • More in-depth information to help you with this transition;
  • HTML content you can put on your website today to minimize unexpected messages to your end users visiting with Google Chrome; and
  • Information about an upcoming Silverlight to HTML5 webinar, scheduled for January 7, 2015.

Our product development team has been working hard since 2011 to help ensure the eventual transition from Silverlight to HTML5 is as smooth as possible for our clients. If you're still deploying public-facing sites and haven't yet completed the majority of your transition to HTML5, we encourage you to make use of the above resources to get applications across the finish line before the end of March.