Do these 3 things before closing this tab:
1Fix the driver behind crashes, sound loss and screen glitches2Clear out junk files and repair common Windows errors3Scan for outdated or missing drivers - takes under a minuteSelenium 4 RC1 was the first release candidate for Selenium 4, announced on September 6, 2021. It previewed relative locators, network interception, and basic or digest authentication. It was a try-it-and-report-issues release, not a stable release or a current recommendation. If you need Selenium now, use the current official Selenium releases and documentation rather than seeking out this historical candidate.
What Selenium 4 RC1 was
RC1 means “release candidate 1”: a pre-release intended for evaluation before a final release. Selenium project contributor Diego Molina announced it on September 6, 2021, with bindings for .NET, Java, Python, Ruby, and JavaScript. The project invited users to try it and report problems. Selenium 4 Release Candidate
As an Amazon Associate I earn from qualifying purchases.
RC1 was followed by Selenium 4 RC2 on October 2, 2021, then Selenium 4.0.0 on October 13, 2021. Those later milestones matter: RC1 was a snapshot in the final lead-up to Selenium 4, not the final version. Selenium 4 Release Candidate 2 · Announcing Selenium 4
What was new in RC1
Relative locators
Relative locators let a test find an element by its position in relation to another element—for example, above or to the right of a known element. This can express a visual relationship directly when a page’s structure makes a conventional locator awkward. The stable Selenium 4 announcement later described relative locators as a way to make tests clearer and more resilient to DOM changes; that is launch-context guidance, not a guarantee that every test becomes more robust.
#1 Best Overall
Network interception
Network interception was among RC1’s stated highlights. The subsequent RC2 announcement describes the capability in terms of capturing and modifying browser HTTP traffic and accessing HTTP status codes. Treat that description as context for the release-candidate series, not as evidence that every network-interception detail was newly added in RC1.
Basic and digest authentication
The release-candidate announcements also called out support for basic or digest authentication. The RC1 announcement does not supply a full usage guide or language-specific code examples, so consult the documentation for the binding and version you actually use rather than inferring an API from the announcement.
Rank #2
How to try RC1 as a 2021 release candidate
At the time of announcement, the Selenium project said RC1 could be obtained through the package manager for its supported language bindings, or downloaded directly from the Selenium site. It named Maven, NuGet, npm, pip, and RubyGems. The announcement did not provide binding-specific install commands, so no exact command should be assumed from that post. The RC1 announcement
Quick wins for a faster PC:
Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →- Identify your binding. Choose the Selenium binding for .NET, Java, Python, Ruby, or JavaScript that matches your test project.
- Use the package source for that language. In the 2021 RC1 context, the project listed NuGet, Maven, pip, RubyGems, and npm, respectively, or a direct download from Selenium.
- Update Firefox’s driver first if relevant. RC1 advised Firefox users to update geckodriver to version 0.29.1 or later before upgrading the Selenium dependency.
- Run your existing test suite and report regressions. A release candidate is for evaluation; test the browser and binding combinations your project depends on before relying on it.
These are historical instructions from September 2021. The available sources do not establish whether RC1 artifacts remain obtainable from every package repository or whether they work with present-day browsers and drivers. They also do not justify substituting later tooling into RC1 setup instructions.
How RC1 differed from RC2 and Selenium 4.0.0
| Release | Date | What the project said | Practical interpretation |
|---|---|---|---|
| Selenium 4 RC1 | September 6, 2021 | First candidate; highlighted relative locators, network interception, and basic or digest authentication. | Early evaluation build; update geckodriver to 0.29.1 or later before upgrading, per the announcement. |
| Selenium 4 RC2 | October 2, 2021 | Second and likely last candidate, with fixes including a fix for CDP-related features breaking when the first window was closed. | A later candidate with feedback-driven fixes; its post told Firefox users to use the latest geckodriver. |
| Selenium 4.0.0 | October 13, 2021 | Stable release. Its announcement covered the Selenium 4 launch and broader features, including a rebuilt Grid. | The final 4.0.0 release, rather than either release candidate, was the stable milestone. |
The Selenium 4.0.0 announcement said the 3.x-to-4.0.0 upgrade aimed to be as simple as changing the dependency, but qualified that guidance: code relying on internal or deprecated APIs could encounter issues. That warning applies to the stable-release upgrade context, not specifically to RC1. The announcement also described Selenium 4 launch-context capabilities such as waiting for DOM changes, viewing JavaScript errors, Grid deployments from single-machine to distributed setups including Kubernetes, GraphQL, live VNC previews, and OpenTelemetry. Do not read that list as a claim that every item was newly introduced in RC1.
Should you install Selenium 4 RC1 now?
For a current project, no: RC1 is a historical pre-release from 2021, and the project subsequently issued RC2 and Selenium 4.0.0. Start with the official Selenium project’s current releases and documentation instead. Use RC1 only if you have a specific historical reproduction or compatibility investigation that requires that exact candidate; availability and compatibility with current browsers are not established by the release announcements.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Or skip the browser setup
If the task is to capture a webpage rather than automate browser interactions, ScreenshotNeo provides a website screenshot API and MCP server. One GET request can return PNG, JPEG, WebP, or PDF. Its capture flow accepts cookie and consent banners like a visitor and removes more than 60 known consent platforms, newsletter popups, and chat widgets; those steps can be turned off. Bot checks, blank pages, timeouts, failed loads, and cache hits are not billed, and responses identify the page verdict and billing status. AI agents can use its MCP server tools: take_screenshot, get_page_info, and capture_pdf.
Recommended Free Tools
cURL example, using the API’s documented parameters (ScreenshotNeo documentation):
curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webpScreenshotNeo includes 1,000 screenshots per month free with no card; paid plans start at $5 for 3,000. Sign up for ScreenshotNeo’s free plan.
Frequently Asked Questions
Which programming languages had Selenium 4 RC1 bindings?
The September 2021 announcement listed .NET, Java, Python, Ruby, and JavaScript.
Was geckodriver 0.29.1 the minimum for all browsers?
No. The RC1 announcement specifically advised updating geckodriver to 0.29.1 or later for Firefox users; it was not a requirement for every browser.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
