Selenium 4.48 Released!

Today we’re happy to announce that Selenium 4.48 has been released!

By Diego Molina @diemol | Thursday, August 27, 2026

Selenium 4.48 Released

BiDi Continued strengthening the shared binding-neutral BiDi layer: Ruby now rejects invalid inbound values (missing required fields, out-of-union scalars, non-whole floats for integer fields), .NET throws on an unknown discriminator, and JavaScript gained a serialization/domain layer plus connection-level event subscription support.
[Ruby] Fixed a silent hang when receiving an oversized WebSocket frame.
[Grid] se:remoteUrl is no longer forwarded past the Node that consumes it, and file upload/download now works for Kubernetes, Docker, and relay sessions.
[.NET] Added the SetMediaFeaturesOverride BiDi command to the Emulation module.
[Python] Fixed W3C capabilities built from a list of options (create_matches).
[JavaScript] Custom locator results are now normalized when empty, and BiDi is no longer exposed on Driver.
[Build & Infra] Added weekly flaky-test reporting, a Slack alert when a CDP update lands on trunk, and fixed the release-workflow issues that broke the previous release.

Fixed two flaky BiDi tests that left timing-dependent state behind.
Added a warning annotation for undeclared fields encountered during JSON coercion.

Fixed W3C capabilities built from a list of options (create_matches).
Fixed a broken reStructuredText link in the docs.
Began generating the internal BiDi protocol layer from the shared binding-neutral schema, updating it to match the latest proposed ADR.

Added low-level BiDi protocol integration specs.
Fixed a silent hang on oversized WebSocket frames.
Fixed intermittent Safari test failures.
Tightened inbound BiDi validation: reject a missing required field, accept whole-valued floats for integer fields, and reject scalars outside a union’s declared arms.

Normalized empty custom locator results.
Ensured BiDi is not exposed on Driver.
Added a BiDi serialization and domain layer, plus connection-level event subscription.

Fixed the issues that broke the release workflow during the last release, and made Java/.NET release reruns pass when already published.
Began recording flaky tests on trunk and reporting weekly offenders to Slack, and alerting Slack when a CDP update lands on trunk.
Reduced GitHub cache churn and aggressively pruned CodeQL caches; fixed the CI build badge on the default branch.
Honored the DO_NOT_TRACK environment variable, and moved dependency updates into a weekly workflow.
Published an ADR on installing browser extensions directly from the driver, and linked the accepted BiDi support boundary record in the project charter.

Docker: Install Edge browser and driver from an archive mirror when Microsoft prunes old versions (#3205)
K8s: Added a configurable securityContext (with seccompProfile) for the external autoscaler (#3199)
See all changes

We thank all our contributors for their incredible efforts in making Selenium better with every release. ❤️

For a detailed look at all changes, check out the release notes.