Back in 2015, Google introduced SPDY as a method of improving TCP connections. HTTP/3 now improves upon that by removing the blocking of TCP with the use of UDP (QUIC).
Firefox: currently disabled by default in version 85, to enable use about:config and set network.http.http3.enabled = true
IOS Safari 14+: currently disabled by default, but can be enabled under Settings > Safari > Advanced > Experimental Features > HTTP/3
Chrome/Chromium: current versions 88+ are currently implementing by default.
Chromium Edge: as new versions are based upon Chromium, support should follow Chrome.
MSIE: was never and will never be implemented.
This was very long overdue for a variety of reasons. While Flash became almost ubiquitous on the web under Macromedia before being acquired by Adobe, it was also full of .
Apple never offered Flash on it’s mobile devices and helped to drive developers to make use of modern HTML5 to accomplish many of the same effects.
Flash “cookies” were buried deep within the application and were not easily removed by users making them very useful for tracking users.
|End of Life Announced
||July 25, 2017
|End of support
||December 31, 2020
||January 12, 2021
There are many files that crawlers expect to find in well-known locations on websites, one such file is ads.txt. While you might not have paid advertisements, crawlers may still look for a copy of this file leading to HTTP 404 errors in your logs. To prevent the error and show that you should have no advertisements leading there you can add the file with placeholder values as follows:
In the root of your website, create a new file with the name ads.txt.
#ads.txt - no DIRECT or RESELLER
www.example.com, placeholder, DIRECT, placeholder
NOTE: If you ever do use an advertiser, they will generally inform you as to changes to make to this file.
This was once a service to aid webmasters with SEO, to claim a website you had to add content to your HTML. While Alexa still provides this service as a subscription, the use of the META tag is no longer required as support was dropped in May 2016!
<meta name="alexaVerifyID" content="your-verification-id-here" />
<a href="..." ping="https://example.com/pingreporter">Example link</a>
The download attribute allows for the downloaded filename to be specified to be something different than the name in the url.
This is available only on the
A tag when an
href attribute is already specified and works similarly to setting the header as:
Content-Disposition: attachment; filename="filename.pdf"
NOTE: this is not currently available in IE, Edge(prior to 13) or IOS Safari.
Silverlight was a browser extension that was backed by Microsoft’s .NET product on many platforms, it provided media capabilities similar to Macromedia/Adobe Flash. Similar to Flash, it has had it’s own share of security problems over the years.
Introduced in 2007 and currently in a deprecated state. Once supported on Windows XP (IE6) to Windows 10 (IE11), MacOS and Ubuntu. Now only supported in MSIE. Edge never provided support. Modern versions of Chrome, Firefox, Safari, and Opera no longer support.
HTML Markup example:
<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
<param name="source" value="MySilverLightControl.xap"/>
I recently crossed paths with a customer that was still using Windows XP and experiencing problems with a website. This led me to evaluate their options for continuing to use this once very common, but now unsupported operating system.
After 12 years, support for Windows XP ended April 8, 2014. Microsoft will no longer provide security updates or technical support.
The most recent version of Internet Explorer in Windows XP was IE 8.0.6001.18702
Even Apple, Google and Mozilla Firefox have ceased to maintain browsers for this operating system, dropping support for Windows XP and Vista at the same time.
Firefox 52.9.0 ESR
An additional problem with use of IE8 on Windows XP is that it only supports up to TLS1.0 which is currently being replaced by TLS1.2 in many web applications.
This practice is now obsolete, and often problematic as there are very few of those browsers in use today – primarily only for testing of legacy functionality.
Example of old approach
// some script
NOTE: for XHTML or XML documents, the use of a CDATA style comment is still required.