Preparing for IE11‘s Retirement: A Veteran Tester‘s Guide to Microsoft Edge Compatibility
Internet Explorer 11 (IE11)‘s looming retirement poses a major challenge for companies still relying on the aging browser. To avoid disruptions, organizations need to assess dependencies, enable compatibility modes, and migrate apps well before IE11 support ends on February 14, 2023.
This comprehensive guide from a veteran testing expert will empower you to meet this deadline with less risk and effort. Follow the best practices below to ensure your web apps and sites transition smoothly to Microsoft Edge.
An Introduction to IE Mode in Edge
Before we dive deeper, let‘s briefly explain this handy feature called "IE mode".
IE mode allows Internet Explorer 11 to be invoked within a separate tab in Microsoft Edge. It renders webpages using an actual IE11 engine while still providing Edge‘s enhanced security and performance for other tabs.
This enables compatibility with legacy IE-dependent apps and websites without impacting your default browsing experience. It will be essential for transitioning off embedded IE11 usage ahead of next year‘s retirement deadline.
To activate it, IT administrators can configure enterprise policies while typical users can simply toggle settings under Edge > Default Browser. Just enable the option to "Reload sites in IE mode", add problem URL patterns, and specified pages will automatically open in an IE-powered tab.
Now let‘s explore more context around IE11‘s phase out and how companies can test and adapt their web tech stack…
The Long Goodbye for Internet Explorer
Internet Explorer dominated the web browser market through the late 90s and 2000s. But growing issues with security vulnerabilities and lack of support for modern web standards soon opened the door to competition.
Alternative browsers leveraged open source development and faster release cycles to rapidly improve compatibility and performance. They also put user experience front and center – areas where IE stagnated.
This table summarizes the key timeline of IE usage and the rise of modern rivals like Chrome and Firefox:
| Year | IE Market Share | Events |
|---|---|---|
| 2003 | 95% | Peak IE dominance |
| 2009 | 65% | Chrome is released |
| 2012 | 40% | Lowest desktop IE share as rivals gain adoption |
| 2015 | 20% | Microsoft releases Edge browser to replace IE |
| 2022 | 4% | IE11 retire date officially announced |
As evident above, IE went from near total domination to becoming largely irrelevant in under 20 years – an amazing fall from grace!
Let‘s analyze the root causes driving this monumental decline…
The Bottlenecks of Legacy Codebases
Internet Explorer originated from Microsoft‘s efforts to bundle a browser with Windows 98 to compete against Netscape Navigator in the first "browser war".
But subsequent releases saw little overhaul of the underlying code. Limitations of the dated layout engine made IE slow to catch up as web standards advanced.
Things like AJAX, new JavaScript APIs, modern encryption standards (TLS 1.3), and much more arrived later sans IE support. Developers increasingly had to program special cases just for IE users.
Meanwhile, open source newcomers built on clean codebases embracing the latest web capabilities. This let users enjoy much faster and reliable experiences accessing their favorite sites and apps.
User Experience Matters!
Simply put – Internet Explorer felt dated compared to nimble competitors. Without an intuitive interface or built-in dev tools, many average users gravitated to slicker alternatives.
And IE‘s integration directly into Windows presented security risks unseen in standalone rivals. Critical patches addressing major vulnerabilities became depressingly routine.
Things we take for granted like tabbed browsing, private modes, bookmarks sync, and robust customization remained sorely lacking in IE for years. Laden with legacy baggage, IE stood little chance catching up.
The Arrival of a New Age
After attempts at reinvigorating IE via projects like IE7 and later IE11, Microsoft needed a fresh start. This birthed Edge – built from the ground up to leave the past behind.
Edge originally used a proprietary layout engine called EdgeHTML. But in 2020, Microsoft controversially swapped to the open source Chromium engine also utilized by Google Chrome. This promised better web standards support and resolved lingering compatibility issues for many modern sites.
For enterprises deeply invested in Microsoft infrastructure though, full migration from IE remains easier said than done…
Assessing Your IE11 Dependencies
Given Internet Explorer‘s presence on Windows desktops for over 20 years, many older internal web apps still rely on quirks in IE to render properly.
IT leaders needing to migrate their tech stacks face non-trivial decisions identifying and resolving all embedded IE dependencies across the broader business.
Let‘s explore best practices that enterprises should adopt starting today:
Inventory Critical Systems
Kick things off by auditing infrastructure to build a manifest of websites, apps, portals, and services requiring IE11 to function:
- Crawl through documentation like technical specifications to flag indicators of IE-only support
- Review testing protocols to find cases dependent on legacy features
- Analyze usage data to reveal hidden IE reliance affecting key workflows
Identifying the scope early allows appropriate prioritization and planning.
Break Down Causes
Next, diagnose what exact compatibility issues make apps IE-only. Common examples include:
- Dependence on ActiveX controls – IE-exclusive binary plug-in technology
- Reliance on legacy IE JavaScript engines like JScript 9
- Failures to handle modern web standards – encrypted connections, new HTML5 elements, etc
Understanding root causes paves the way to solving through migration paths or temporary workarounds.
Assess Migration Costs
With issues enumerated, weigh thecodebase changes needed to modernize each system.
Consider timelines, level of effort, budgets, and risks involved. Also factor in downstream impacts on associated infrastructure.
This analysis guides strategic platform overhaul investments versus opting for short-term fixes like IE mode.
Equipped with assesssments of inventory, causes and migration viability, we can now act to address looming compatibility issues…
Utilizing IE Mode as a Short-Term Bridge
For legacy systems proving cost-prohibitive to fully modernize prior to next February, IE mode offers a handy stopgap:
What is IE Mode Exactly?
This feature available within Microsoft Edge taps an IE11 rendering engine strictly for backward compatibility.
It sandboxes legacy IE11 behavior to specific sites/web apps without compromising improved security and standards support of the surrounding Edge browser.
Individual tab processes invoke IE but otherwise general browsing leverages Edge‘s modern Chromium foundation.
Common Activation Methods
Users and admins can force IE mode a few ways:
- Configure domain allow list policies – apply IE rendering strictly to listed sites
- Extend IE legacy lifecycle support – defer IE11 phase out across Windows estate
- Toggle IE mode in Edge settings – enable per-site activation as needed
Match approach to the limitations and use cases unique to your technical environment.
What to Test in IE Mode
Whatever the technique, be sure to thoroughly vet IE mode interoperability for:
- User login and authentication flows
- Site layout, styling and responsiveness
- Support for legacy plugins like Silverlight or ActiveX
- Error handling for unsupported features
- Performance parity with native IE11
Compare against an IE11 baseline on legacy Windows versions using BrowserStack if needed.
Address regressions by adjusting Enterprise Site List definitions or utilizing polyfills.
Migrating Strategically Ahead of February 2023
Relying solely on IE mode long-term has downsides, namely continued security risks requiring expensive mitigations.
Use the next 12 months to overhaul true IE dependencies where feasible:
Typical Remediation Paths
- Codebase refactors – rewrite handling of proprietary IE-only APIs
- Web standard shims – polyfill libraries adding missing browser support
- Transpilers (Babel) – convert JS reliant on legacy IE engines
- Virtualization – containerize legacy apps to isolate OS dependencies
Prioritize Smooth User Transitions
Don‘t underestimate disruptions users accustomed to IE11 may experience. Education and empathy is key:
- Develop training programs on changes coming to internal web systems
- Highlight benefits – improved stability, security, speed
- Share resources & FAQs to get ahead of complaints and tickets
Proactively smooth adoption curves to avoid backlash derailing projects.
The Promise (and Peril) of Chromium
While Edge‘s transition to the Chromium engine promises better standards support, risks remain:
- Codebase governed by Google with opaque roadmap
- Fewer browsing engine diversity aids Google market dominance
- Potential for a less competitive/innovative web ecosystem
Remain vigilant of this factor when choosing strategic migration paths.
Expert Testing Tips and Tricks
Specialized testing is mandatory to safely retire IE11 across Windows estates by February 2023. Here are pro tips from my decade-plus of experience:
Leverage Real Browser Testing Services
Platforms like BrowserStack grant affordable on-demand access to thousands of real browser and OS combinations – including IE11.
Validate compatibility without needing to maintain complex lab infrastructure.
Compare Baselines Meticulously
Rigorously document current IE11 behavior including certificates, network calls, page load times, visual defects, and more.
Use this baseline to catch compatibility regressions during and after migrations to Edge or Chrome.
Automate Testing Workflows
Manually confirming each web property across every scenario is time-prohibitive.
Automated tests running on virtual test beds around the clock is far more scaleable.
Embrace Progressive Web App Strategies
Modern "PWA" techniques like service workers, cache APIs, and responsive design best equip apps to handle IE11‘s retirement.
Build resilience against dependency issues using standards-based coding patterns.
Start Testing Yesterday!
Complex enterprises can ill afford delaying necessary upgrades. Begin assessments now before time runs short!
Stay a step ahead rather than allowing technical debt to compound further.
While Edge and Chromium at large fill IE11‘s fading shoes, exercising diligence smoothing this browser transition remains vital.
Heed the tips outlined above to best secure your organization‘s digital future beyond next February and IE‘s long overdue retirement.
You‘ve got this! Now onward…